Agilent X-Series Signal Generators N5171B/72B/73B EXG N5181B/82B/83B MXG User’s Guide Agilent Technologies
Notices © Agilent Technologies, Inc. 2014 Warranty No part of this manual may be reproduced in any form or by any means (including electronic storage and retrieval or translation into a foreign language) without prior agreement and written consent from Agilent Technologies, Inc. as governed by United States and international copyright laws. The material contained in this document is provided “as is,” and is subject to being changed, without notice, in future editions.
Contents 1 Signal Generator Overview Signal Generator Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 Modes of Operation . . Continuous Wave . Swept Signal . . . . Analog Modulation Digital Modulation . . . . . . . . . . . . . . . . . . . . (Vector . . . . . . . . . . . . . . . . . . . . Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . with Option 65x Only) . . .
Contents 2. EXT 1 & EXT 2 . . . . . . . . 3. LF OUT . . . . . . . . . . . . . 4. SWEEP OUT . . . . . . . . . . 5. PULSE . . . . . . . . . . . . . . 6. TRIG 1 & 2 . . . . . . . . . . . 7. REF IN . . . . . . . . . . . . . . 8. 10 MHz OUT . . . . . . . . . . 9. GPIB . . . . . . . . . . . . . . . 10. LAN . . . . . . . . . . . . . . . 11. Device USB . . . . . . . . . . 12. Host USB . . . . . . . . . . . 13. SD Card . . . . . . . . . . . . Digital Modulation Connectors I OUT, Q OUT, OUT, OUT . .
Contents Setting Time and Date. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Reference Oscillator Tune . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Upgrading Firmware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Remote Operation Preferences . . . . . . . . . . . . . . . . . . . . . . GPIB Address and Remote Language . . . . . . . . . . . . . . .
Contents Working with Instrument State Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 Selecting the Default Storage Media. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 Reading Error Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 Error Message Format. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Contents Using Free Run, Step Dwell, and Timer Trigger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 Understanding Free Run, Step Dwell, and Timer Trigger Setup . . . . . . . . . . . . . . . . . . 126 Using a USB Keyboard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 6 Using Pulse Modulation (Option UNW or 320) Pulse Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Contents Using the RF Blanking Marker Function. . . . . . . Setting Marker Polarity . . . . . . . . . . . . . . . . . . Controlling Markers in a Waveform Sequence . . . Using the EVENT Output Signal as an Instrument Triggering a Waveform . . . . . . . . . . . . . Trigger Type . . . . . . . . . . . . . . . . . Trigger Source . . . . . . . . . . . . . . . . Example: Segment Advance Triggering Example: Gated Triggering . . . . . . . . Example: External Triggering . . . . . . . . . . . . . . . . . . . . . .
Contents Making Changes to the Multiple Synchronization Setup and Resynchronizing the Master/Slave System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231 Understanding Option 012 (LO In/Out for Phase Coherency) with Multiple Baseband Generator Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232 Configuring the Option 012 (LO In/Out for Phase Coherency) with MIMO . . . . .
Contents Choosing the Logic Type and Port Configuration . Configuring the Clock Signal . . . . . . . . . . . . . . Selecting the Data Parameters . . . . . . . . . . . . . Digital Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282 283 287 290 . . . . . . . . . . . . .
Contents Recalling a User- Defined Burst Shape Curve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335 Using the Arbitrary Waveform Generator . . . . . . . . . . . . . . . . . . . . . . Using Predefined Custom Digital Modulation . . . . . . . . . . . . . . . . . Creating a Custom Digital Modulation State . . . . . . . . . . . . . . . . . Storing a Custom Digital Modulation State . . . . . . . . . . . . . . . . . . Recalling a Custom Digital Modulation State . . . . . . . . . . . . . . . . .
Contents Using Secure Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 380 16 Troubleshooting Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 382 The Display is Too Dark to Read . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 382 The Display Turns Black when Using USB Media. . . . . . . . . . . . . . . . . . . . . . . . . . .
Documentation Overview Getting Started Guide User’s Guide Programming Guide • • • • • • • Safety Information • • • • • • • • • • • • • • Signal Generator Overview • • • • • • Getting Started with Remote Operation Receiving the Instrument Environmental & Electrical Requirements Basic Setup Accessories Operation Verification Regulatory Information Setting Preferences & Enabling Options Basic Operation Optimizing Performance Using Analog Modulation (Option UNT) Using Pulse Modulation (Option UNW and
SCPI Reference • • • • • • • SCPI Basics Basic Function Commands LXI System Commands System Commands Analog Modulation Commands Arb Commands Real–Time Commands Programming Compatibility Guide Provides a listing of SCPI commands and programming codes for signal generator models that are supported by the Agilent EXG and MXG X- Series signal generators.
1 Signal Generator Overview CAUTION To avoid damaging or degrading the performance of the instrument, do not exceed 33 dBm (2W) maximum (27 dBm (0.5W) for N5173N/83B) of reverse power levels at the RF input. See also Tips for Preventing Signal Generator Damage on www.agilent.com.
Signal Generator Overview Signal Generator Features Signal Generator Features • N5171B/N5181B, RF analog models: 9 kHz to 1 (N5171B only), 3, or 6 GHz (Options 501, 503, and 506 respectively) • N5172B/N5182B, RF vector models: 9 kHz to 3 or 6 GHz (Options 503, and 506 respectively) • N5173B/N5183B, Microwave analog models: 9 kHz to 13, 20, 31.
Signal Generator Overview Signal Generator Features • flexible reference input, 1 – 50 MHz (Option 1ER) • LO In/Out for phase coherency (Option 012) • phase noise interference (vector models, Option 432) • expanded license key upgradability (Option 099) For more details on hardware, firmware, software, and documentation features and options, refer to the data sheet shipped with the signal generator and available from the Agilent Technologies website at http://www.agilent.com/find/X- Series_SG.
Signal Generator Overview Modes of Operation Modes of Operation Depending on the model and installed options, the Agilent X- Series signal generator provides up to four basic modes of operation: continuous wave (CW), swept signal, analog modulation, and digital modulation. Continuous Wave In this mode, the signal generator produces a continuous wave signal. The signal generator is set to a single frequency and power level. Both the analog and vector models can produce a CW signal.
Signal Generator Overview Front Panel Overview • Two–tone mode produces two separate continuous wave signals (or tones). The frequency spacing between the signals and the amplitudes are adjustable. To learn more, refer to Chapter 14, "Multitone and Two–Tone Waveforms (Option 430)". • Dual ARB mode is used to control the playback sequence of waveform segments that have been written into the ARB memory located on the internal baseband generator.
Signal Generator Overview Front Panel Overview indicators, frequency and amplitude settings, and error messages. Labels for the softkeys are located on the right hand side of the display. See also, “Front Panel Display” on page 10. 3. Softkeys A softkey activates the function indicated by the displayed label to the left of the key. 4. Numeric Keypad The numeric keypad comprises the 0 through 9 hardkeys, a decimal point hardkey, a minus sign hardkey, and a backspace hardkey.
Signal Generator Overview Front Panel Overview 8. Trigger When trigger mode is set to Trigger Key, this hardkey initiates an immediate trigger event for a function such as a list or step sweep. 9. Local Cancel/(Esc) This hardkey deactivates remote operation and returns the signal generator to front panel control, cancels an active function entry, and cancels long operations (such an IQ calibration). 10. Help Use this key to display a description of any hardkey or softkey.
Signal Generator Overview Front Panel Overview NOTE The Mod On/Off hardkey and LED functionality are only valid for instruments with Option UNT installed. 15. Page Down In a table editor, use this hardkey to display the next page. See “Example: Using a Table Editor” on page 46. When text does not fit on one page in the display area, use this key in conjunction with the Page Up key (page 6) to scroll text. 16.
Signal Generator Overview Front Panel Overview message displays below the labels. To display the next group of labels, press the More hardkey. 22. Power Switch and LEDs This switch selects the standby mode or the power on mode. In the standby position, the yellow LED lights and all signal generator functions deactivate. The signal generator remains connected to the line power, and some power is consumed by some internal circuits.
Signal Generator Overview Front Panel Display Front Panel Display 1. Active Function Area 2. Frequency Area 3. Annunciators 4. Amplitude Area Scroll Bar If there is more text than can be displayed on one screen, a scroll bar appears here. Use the Page Up and Page Down keys to scroll through the text. 5. Error Message Area 6. Text Area 7. Softkey Label Area 1. Active Function Area This area displays the currently active function.
Signal Generator Overview Front Panel Display This annunciator appears when... BBG DAC A DAC overflow is occurring, adjust the runtime scaling adjust until the BBG DAC annunciator turns off. Another annunciator, UNLOCK, appears in the same position and has priority over the BBG DAC annunciator (see UNLOCK, below). CHANCORR The internal channel correction is enabled. DETHTR The ALC detector heater is not up to temperature. To meet ALC specifications the heater must be at temperature.
Signal Generator Overview Front Panel Display 5. Error Message Area This area displays abbreviated error messages. If multiple messages occur, only the most recent message remains displayed. See “Reading Error Messages” on page 73. 6. Text Area This area displays signal generator status information, such as the modulation status, and other information such as sweep lists and file catalogs.
Signal Generator Overview Rear Panel Overview (N5171B, N5172B, N5181B, & N5182B) Rear Panel Overview (N5171B, N5172B, N5181B, & N5182B) 1. AC Power Receptacle Digital Modulation Connectors (Vector Models Only) on page 16 Option 1EM only See page 7 3. LF OUT 2. EXT 1 & EXT 2 6. TRIG 1 & 2 5. PULSE 4. SWEEP OUT 9. GPIB 10. LAN 8. 10 MHz OUT 7. REF IN 13. SD Card 12. Host USB 11. Device USB 1.
Signal Generator Overview Rear Panel Overview (N5171B, N5172B, N5181B, & N5182B) 2. EXT 1 & EXT 2 Impedance nominally 50 Ω Connector female BNC Signal An externally supplied ±1 Vp signal that produces the indicated depth. Damage Levels 5 Vrms and 10 Vp 3. LF OUT Impedance 50 Ω Connector female BNC Signal Voltage range: 0 to +5 Vp Offset: - 5 V to +5 V, nominal For more information, see page 81. 4. SWEEP OUT Impedance <1 Ω Connector female BNC Can drive 2 kΩ.
Signal Generator Overview Rear Panel Overview (N5171B, N5172B, N5181B, & N5182B) panel or over the remote interface. 8. 10 MHz OUT Impedance nominally 50 Ω Connector female BNC Signal A nominal signal level greater than 4 dBm. 9. GPIB This connector enables communication with compatible devices such as external controllers, and is one of three connectors available to remotely control the signal generator (see also 10. LAN and 11. Device USB). 10.
Signal Generator Overview Rear Panel Overview (N5171B, N5172B, N5181B, & N5182B) Digital Modulation Connectors (Vector Models Only) I OUT, Q OUT, I OUT, Q OUT NOTE I OUT and Q OUT, require Option 1EL. Connector Type: female BNC DC–coupled Impedance: 50 Ω Signal I OUT The analog, in–phase component of I/Q modulation from the internal baseband generator. Q OUT The analog, quadrature–phase component of I/Q modulation from the internal baseband generator.
Signal Generator Overview Rear Panel Overview (N5171B, N5172B, N5181B, & N5182B) BB TRIG 1 & BB TRIG 2 Impedance nominally 50 Ω Connector female BNC Signal Reserved for arbitrary and real- time baseband generators I/O, such as markers or trigger inputs. EVENT 1 Connector female BNC Impedance: nominally 50 Ω Signal A pulse that can be used to trigger the start of a data pattern, frame, or timeslot.
Signal Generator Overview Rear Panel Overview (N5171B, N5172B, N5181B, & N5182B) AUX I/O Connector This female 36- pin connector is available only on instruments with an internal baseband generator (Option 653, 655, 656, 657). On signal generators without one of these options, this connector is not present. The AUX I/O connector allows the X- Series signal generator to interface with external equipment by sending and/or receiving supplementary (auxiliary) signaling information.
Signal Generator Overview Rear Panel Overview (N5171B, N5172B, N5181B, & N5182B) Markers (pins 1-4) Each Arb–based waveform point has a marker on/off condition associated with it. Each real-time signal can be routed to the output marker signals using SCPI commands or the real-time personalities. Marker level = +3.3 V high (positive polarity selected); 0V low (negative polarity selected). Event 1 (pin 1) Pin 1 outputs a pulse that can be used to trigger the start of a data pattern, frame, or timeslot.
Signal Generator Overview Rear Panel Overview (N5171B, N5172B, N5181B, & N5182B) Table 1-1 AUX I/O Connector Configuration MXG and EXG AUX I/O Connector Configuration Pin # ARB & ARB- Based Applications Real- Time Custom Modulation Input Input Output Output Real- Time Applications Input Event 1 Output 1 Marker(1) 2 Marker(2) Marker(2) 3 Marker(3) Marker(3) 4 Marker(4) Marker(4) BERT Capability Input Output Marker(1) 5 AUX Strobe 6 7 Data Clock Output 10MHz Clock 8 AUX(0) 9
Signal Generator Overview Rear Panel Overview (N5171B, N5172B, N5181B, & N5182B) Table 1-1 AUX I/O Connector Configuration MXG and EXG AUX I/O Connector Configuration Pin # ARB & ARB- Based Applications Real- Time Custom Modulation Input Input Output Output Real- Time Applications Input Output AUX(9) 17 BERT Capability Input Output BER Test Outa AUX(10) 18 BER Gate Outa AUX(11) 19 BER No Dataa 20 GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND
Signal Generator Overview Rear Panel Overview (N5171B, N5172B, N5181B, & N5182B) Table 1-1 AUX I/O Connector Configuration MXG and EXG AUX I/O Connector Configuration Pin # 32 ARB & ARB- Based Applications Real- Time Custom Modulation Input Input GND Output GND GND GND GND GND GND GND GND GND GND GND Output BERT Capability Input Output GND AUX Out(1) GND Symbol Sync Output 35 36 GND Input Data Out 33 34 Output Real- Time Applications GND AUX Out(2) GND GND aSettings sho
Signal Generator Overview Rear Panel Overview (N5173B & N5183B) Rear Panel Overview (N5173B & N5183B) 14. ALC INPUT 1. AC Power Receptacle 15. Z AXIS Option 1EM only See page 7 3. LF OUT 2. EXT 1 & EXT 2 6. TRIG 1 & 2 5. PULSE 9. GPIB 10. LAN 8. 10 MHz OUT 7. REF IN 13. SD Card 12. Host USB 11. Device USB 4. SWEEP OUT 1. AC Power Receptacle The AC power cord receptacle accepts a three–pronged AC power cord that is supplied with the signal generator.
Signal Generator Overview Rear Panel Overview (N5173B & N5183B) 2. EXT 1 & EXT 2 Impedance nominally 50 Ω Connector female BNC Signal An externally supplied ±1 Vp signal that produces the indicated depth. Damage Levels 5 Vrms and 10 Vp 3. LF OUT Impedance 50 Ω Connector female BNC Signal Voltage range: 0 to +5 Vp Offset: - 5 V to +5 V, nominal For more information, see page 81. 4. SWEEP OUT Impedance <1 Ω Connector female BNC Can drive 2 kΩ.
Signal Generator Overview Rear Panel Overview (N5173B & N5183B) panel or over the remote interface. 8. 10 MHz OUT Impedance nominally 50 Ω Connector female BNC Signal A nominal signal level greater than 4 dBm. 9. GPIB This connector enables communication with compatible devices such as external controllers, and is one of three connectors available to remotely control the signal generator (see also 10. LAN and 11. Device USB). 10.
Signal Generator Overview Rear Panel Overview (N5173B & N5183B) 15. Z AXIS OUTPUT This female BNC connector supplies a +5 V (nominal) level during retrace and band- switch intervals of a step or list sweep. During step or list sweep, this female BNC connector supplies a - 5 V (nominal) level when the RF frequency is at a marker frequency and intensity marker mode is on. This signal is derived from an operational amplifier output so the load impedance should be greater than or equal to 5 kohms.
2 Setting Preferences & Enabling Options The Utility menu provides access to both user and remote operation preferences, and to the menus in which you can enable instrument options.
Setting Preferences & Enabling Options User Preferences User Preferences From the Utility menu, you can set the following user preferences: • Display Settings, below • Power On and Preset on page 29 • Front Panel Knob Resolution on page 30 Display Settings NOTE X- Series signal generators are shipped from the factory with default display settings. Automated Test Environment (ATE) users may benefit from display settings other than the default settings.
Setting Preferences & Enabling Options User Preferences Power On and Preset Utility > Power On/Preset Restores persistent settings (those unaffected by a power cycle*, preset, or recall) to their factory defaults. Select the GPIB language desired after a preset. See also, the Programming Guide and the SCPI Command Reference. Available only when 8648 is either the selected preset language or the selected remote language (see page 32).
Setting Preferences & Enabling Options User Preferences Front Panel Knob Resolution Makes the increment value of the current function the active entry. Utility > Instrument Adjustments The increment value and the step/knob ratio determine how much each turn of the knob changes the active function value. For example, if the increment value of the active function is 10 dB and the step/knob ratio is 50 to 1, each turn of the knob changes the active function by 0.2 dB (1/50th of 10 dB). page 30. page 31.
Setting Preferences & Enabling Options Upgrading Firmware time back. In this case, you can re- enable the signal generator’s ability to use time–based licenses by moving the clock forward to the original time or simply waiting that length of time. Reference Oscillator Tune Utility > Instrument Adjustments Tunes the internal VCTXCO oscillator frequency. The user value offsets the factory tuned value (the value is added to the factory calibrated DAC value).
Setting Preferences & Enabling Options Remote Operation Preferences Remote Operation Preferences For details on operating the signal generator remotely, refer to the Programming Guide. GPIB Address and Remote Language NOTES USB is also available. It is not shown in the menu because it requires no configuration. For details on using the instrument remotely, see the Programming Guide. page 33 page 34 Select the desired language.
Setting Preferences & Enabling Options Remote Operation Preferences Configuring the LAN Interface Utility > I/O Config page 34. NOTES Use a 100Base–T LAN cable to connect the signal generator to the LAN. Use a crossover cable to connect the signal generator directly to a PC. For details on using the instrument remotely, refer to the Programming Guide and to www.agilent.com and search on FAQs: Hardware Configurations and Installation for the Agilent MXG.
Setting Preferences & Enabling Options Remote Operation Preferences Enabling LAN Services: “Browser,” “Sockets,” and “VXI–11” Utility > I/O Config Enable remote (browser) access to the instrument’s file system. Use a browser to control the signal generator. License Manager Server (On) allows updates of the instrument licenses, disable for additional instrument security. For details on each key, use key help as described on page 44. 34 For more information refer to the Programming Guide.
Setting Preferences & Enabling Options Remote Operation Preferences Configuring the Remote Languages Figure 2-1 N5171B/72B/81B/82B Utility > I/O Config For details on each key, use key help as described on page 44. Agilent X-Series Signal Generators User’s Guide Select the desired Remote language. Refer to the SCPI Command Reference.
Setting Preferences & Enabling Options Remote Operation Preferences Figure 2-2 N5173B/83B Utility > I/O Config Select the desired Remote language. For details on each key, use key help as described on page 44. Refer to the SCPI Command Reference.
Setting Preferences & Enabling Options Remote Operation Preferences Configuring the Preset Languages Figure 2-3 N5171B/72B/81B/82B Utility > Power On/Preset Select the desired Remote language. page 29 For details on each key, use key help as described on page 44. Agilent X-Series Signal Generators User’s Guide Refer to the SCPI Command Reference.
Setting Preferences & Enabling Options Remote Operation Preferences Figure 2-4 N5173B/83B Utility > Power On/Preset Select the desired Remote language. page 29 For details on each key, use key help as described on page 44. Refer to the SCPI Command Reference.
Setting Preferences & Enabling Options Enabling an Option Enabling an Option There are two ways to enable an option: • Use the License Manager software utility: 1. Run the utility and follow the prompts. 2. Download the utility from www.agilent.com/find/LicenseManager and select license (.lic) files from an external USB Flash Drive (UFD). • Use SCPI commands, as described in the Programming Guide.
Setting Preferences & Enabling Options Enabling an Option Viewing Options and Licenses Utility > Instrument Info Service Software Licenses appear here. Instrument options appear here. A check mark means that an option is enabled. Waveform licenses from some Signal Studio applications appear here. For details on each key, use key help as described on page 44.
Setting Preferences & Enabling Options Hardware Assembly Installation and Removal Softkeys Hardware Assembly Installation and Removal Softkeys Utility > More 2 of 2 > Service Verify output attenuator operation using a power meter at the RF Output. Select either Enhanced Factory Calibration or Factory Calibration to calibrate your instrument. For details on each key, use key help as described on page 44. Whether a softkey is available depends on the model of signal generator.
Setting Preferences & Enabling Options Hardware Assembly Installation and Removal Softkeys 42 Agilent X-Series Signal Generators User’s Guide
3 Basic Operation This chapter introduces fundamental front panel operation. For information on remote operation, refer to the Programming Guide.
Basic Operation Presetting the Signal Generator Presetting the Signal Generator To return the signal generator to a known state, press either Preset or User Preset. Preset is the factory preset; User Preset is a custom preset** (see also, page 29). To reset persistent settings (those unaffected by preset, user preset, or power cycle*), press: Utility > Power On/Preset > Restore System Defaults.
Basic Operation Entering and Editing Numbers and Text Entering and Editing Numbers and Text Entering Numbers and Moving the Cursor Use the number keys and decimal point to enter numeric data. Up/down arrow keys increase/decrease a selected (highlighted) numeric value, and move the cursor vertically. Page up/down keys move tables of data up and down within the display area. Left/right arrow keys move the cursor horizontally.
Basic Operation Entering and Editing Numbers and Text Example: Using a Table Editor Table editors simplify configuration tasks. The following procedure describes basic table editor functionality using the List Mode Values table editor. 1. Preset the signal generator: Press Preset. 2. Open the table editor: Press Sweep > More > Configure List Sweep. The signal generator displays the editor shown in the following figure. Active Function Area Displays the active item as you edit it.
Basic Operation Setting Frequency and Power (Amplitude) Setting Frequency and Power (Amplitude) Figure 3-1 Frequency and Amplitude Softkeys In Frequency mode, this menu is automatically displayed when entering a numeric value with the front panel keypad. In Amplitude mode, this menu is automatically displayed when entering a numeric value with the front panel keypad. Opens the Atten/ALC Control menu. page 122 dBuVemf terminates the value as dBuV electromotive force.
Basic Operation Setting Frequency and Power (Amplitude) Example: Configuring a 700 MHz, −20 dBm Continuous Wave Output 1. Preset the signal generator. The signal generator displays its maximum specified frequency and minimum power level (the front panel display areas are shown on page 10). 2. Set the frequency to 700 MHz: Press Freq > 700 > MHz. The signal generator displays 700 MHz in both the FREQUENCY area of the display and the active entry area. 3.
Basic Operation Setting ALC Bandwidth Control Figure 3-2 Using an External Reference Oscillator Setting ALC Bandwidth Control Figure 3-3 Amplitude Softkeys Enables the automatic ALC bandwidth mode (Auto). For details on each key, use key help as described on page 44. Refer to the SCPI Command Reference. Agilent X-Series Signal Generators User’s Guide To display the next menu, press More.
Basic Operation Configuring a Swept Output Configuring a Swept Output The signal generator has two methods of sweeping through a set of frequency and amplitude points: Step sweep (page 52) provides a linear or logarithmic progression from one selected frequency, amplitude, or both, to another, pausing at linearly or logarithmically spaced points (steps) along the sweep. The sweep can progress forward, backward, or manually.
Basic Operation Configuring a Swept Output Figure 3-4 Sweep Softkeys During a sweep, the swept parameter (frequency, amplitude, or both) turns grey and changes as the parameter sweeps. The selected sweep type determines the displayed parameter. Selecting step sweep also displays the step spacing (Lin or Log). Progress Bar: Note that very fast sweeps can appear to sweep randomly or backward. page 52 Sweep without waiting for a trigger at each point.
Basic Operation Configuring a Swept Output Routing Signals Sweep > More > More > Route Connectors Step Sweep Step sweep provides a linear or logarithmic progression from one selected frequency, or amplitude, or both, to another, pausing at linearly or logarithmically spaced points (steps) along the sweep. The sweep can progress forward, backward, or be changed manually. Figure 3-5 Signal Routing Softkeys Routes Step or List Sweep signals. Routes non Step or List Sweep signals (i.e.
Basic Operation Configuring a Swept Output Figure 3-6 Sweep Softkeys For details on each key, use key help as described on page 44. Dwell Time = the time that the signal is settled and you can make a measurement before the sweep moves to the next point. (Point to point time is the sum of the value set for the dwell plus processing time, switching time, and settling time.) Step Sweep and List Sweep dwell times are set Lin = steps equally spaced over the sweep; the output changes linearly.
Basic Operation Configuring a Swept Output 4. Sweep both frequency and amplitude: Press Return > Return > Sweep > Freq Off On > Amptd Off On. A continuous sweep begins, from the start frequency/amplitude to the stop frequency/amplitude. The SWEEP annunciator displays, and sweep progress is shown in the frequency display, the amplitude display, and the progress bar. 5. Turn the RF output on: Press RF On/Off. The RF LED lights, and the continuous sweep is available at the RF Output connector.
Basic Operation Configuring a Swept Output List Sweep List sweep enables you to enter frequencies and amplitudes at unequal intervals in nonlinear ascending, descending, or random order. List sweep also enables you to copy the current step sweep values, include a waveform in a sweep (on a vector instrument), and save list sweep data in the file catalog (page 66). Dwell time is editable at each point. For fastest switching speeds, use list sweep.
Basic Operation Configuring a Swept Output Example: Configuring a List Sweep Using Step Sweep Data 1. Set up the desired step sweep, but do not turn the sweep on. This example uses the step sweep configured on page 53. 2. In the SWEEP menu, change the sweep type to list: Press SWEEP > Sweep Type List Step to highlight List. The display shows sweep list parameters, as shown below. 3. Open the List Sweep menu: Press More > Configure List Sweep. 4.
Basic Operation Configuring a Swept Output Example: Editing List Sweep Points If you are not familiar with table editors, refer to page 46. 1. Create the desired list sweep. This example uses the list sweep created in the previous example. 2. If sweep is on, turn it off. Editing list sweep parameters with sweep on can generate an error. 3. Ensure that the sweep type is set to list: Press SWEEP > Sweep Type List Step to highlight List. 4.
Basic Operation Configuring a Swept Output 13. As desired, repeat step 12 for the remaining points for which you want to select a waveform. The following figure shows an example of how this might look. The empty entry is equivalent to choosing CW (no modulation). 14. Turn sweep on: Press Return > Return > Return > Sweep > Freq Off On > Amptd Off On > Waveform Off On. 15. If it is not already on, turn the RF output on: Press RF On/Off.
Basic Operation Modulating the Carrier Signal Example: Manual Control of Sweep 1. Set up either a step sweep (page 53) or a list sweep (page 56). 2. In the Sweep/List menu, select a parameter to sweep: Press Sweep > parameter > Return. 3. Select manual mode: Press More > Manual Mode Off On. When you select manual mode, the current sweep point becomes the selected manual point. 4. If it is not already on, turn the RF output on: Press RF On/Off. 5.
Basic Operation Modulating the Carrier Signal 3. Enable modulation of the RF output: Press the Mod On/Off key until the LED lights. If you enable modulation without an active modulation format, the carrier signal does not modulate until you subsequently turn on a modulation format. Annunciator indicates active AM modulation A lit LED indicates that any active modulation format can modulate the carrier. AM modulation format on.
Basic Operation Working with Files Simultaneous Modulation NOTE The Agilent X- Series signal generators are capable of simultaneous modulation. All modulation types (AM, FM, φM, Pulse, and I/Q) may be simultaneously enabled, but there are some exceptions. Refer to Table 3- 1.
Basic Operation Working with Files File Softkeys For details on each key, use key help as described on page 44. Note: Available file types depend on the installed options. Instrument operating parameters (see page 68). Display internal or USB files, depending on the selected storage media. Sweep data from the List Mode Values table editor. User flatness calibration corrections. page 63 Displays IQ Files Deletions require confirmation.
Basic Operation Working with Files ARB File Softkeys Waveform files and their associated marker and header information. Note: Available file types depend on the installed options. For details on each key, use key help as described on page 44. Viewing a List of Stored Files The information in this section is provided with the assumption that default storage media is set to Auto, as described on page 72. Viewing a List of Files Stored in the Signal Generator 1. If USB media is connected, disconnect it.
Basic Operation Working with Files Viewing a list of Files Stored on USB Media With USB media connected, you can view files on USB media using either the file catalogs, which can display only a selected type of file, or the USB File Manager, which displays all files. Using the File Catalogs: • With the USB media connected, select the desired file catalog: press > Catalog Type > desired catalog. The selected files appear in alphabetical order by file name.
Basic Operation Working with Files Storing a File Several menus enable you to store instrument parameters. For example, you can store instrument states, lists, and waveforms. • An instrument state file contains instrument settings. For this type of file, use the Save hardkey shown in Figure 3- 8 on page 68. • For other types of data, use the Load/Store softkey (shown below) that is available through the menu used to create the file.
Basic Operation Working with Files Loading (Recalling) a Stored File There are several ways to load (recall) a stored file. • For an instrument state file, use the Recall hardkey shown in Figure 3- 8 on page 68. • For other types of data, use the Load/Store softkey (shown below) that is available through the menu used to create the file.
Basic Operation Working with Files Moving a File from One Media to Another Use the USB Media Manager to move files between USB and internal media. File > Catalog Type > > More > USB File Manager or File > More > USB File Manager or Selecting a waveform or Insert the USB Flash Drive (UFD) an unknown file type displays this softkey. This key changes, depending on the selected file. See page 66 Whether a menu is available depends on the selected file.
Basic Operation Working with Files Working with Instrument State Files • Saving an Instrument State on page 69 • Saving a User Preset on page 69 • Recalling an Instrument State on page 69 • Recalling an Instrument State and Associated Waveform File on page 70 • Recalling an Instrument State and Associated List File on page 70 • Moving or Copying a Stored Instrument State on page 71 Figure 3-8 Save and Recall Softkeys When saved to the signal generator, instrument settings (states) save to instrument state
Basic Operation Working with Files Saving an Instrument State 1. Preset the signal generator and set the following: • Frequency: 800 MHz • Amplitude: 0 dBm • RF: on 2. (Optional, vector models only) Associate a waveform file with these settings: a. Press Mode > Dual ARB > Select Waveform. b. Highlight the desired file and press Select Waveform. If the file is not listed, you must first move it from internal or external media to BBG media, see page 148. 3.
Basic Operation Working with Files Recalling an Instrument State and Associated Waveform File 1. Ensure that the desired waveform file exists, and that it is in BBG media (page 148). If the waveform file is not in BBG media, this procedure generates an error. Recalling an instrument state with an associated waveform file recalls only the waveform name. It does not recreate the waveform file if it was deleted, or load the file into BBG media if it is in internal or USB media. 2.
Basic Operation Working with Files Moving or Copying a Stored Instrument State Figure 3-9 Instrument State File Catalog Sequence Register The signal generator recognizes only the file named USER_PRESET as user preset information (page 69). A user–created state file’s default name is its memory location (sequence and register). To move the file, rename it to the desired sequence and register; you can not give a file the same name as an existing file.
Basic Operation Working with Files Selecting the Default Storage Media You can configure the signal generator to store user files to either the internal storage or to external USB media. To automatically switch between USB media and internal storage, depending on whether USB media is attached, select Automatically Use USB Media If Present. To avoid storing any confidential information in the instrument, select Use Only USB Media.
Basic Operation Reading Error Messages Reading Error Messages If an error condition occurs, the signal generator reports it to both the front panel display error queue and the SCPI (remote interface) error queue. These two queues are viewed and managed separately; for information on the SCPI error queue, refer to the Programming Guide. Characteristic Capacity (#errors) 30 Overflow Handling Drops the oldest error as each new error comes in.
Basic Operation Reading Error Messages 74 Agilent X-Series Signal Generators User’s Guide
4 NOTE Using Analog Modulation (Option UNT) The Mod On/Off hardkey and LED functionality are only valid for signal generators with Option UNT installed. Before using this information, you should be familiar with the basic operation of the signal generator. If you are not comfortable with functions such as setting the power level and frequency, refer to Chapter 3, “Basic Operation,” on page 43 and familiarize yourself with the information in that chapter.
Using Analog Modulation (Option UNT) Analog Modulation Waveforms Analog Modulation Waveforms The signal generator can modulate the RF carrier with four types of analog modulation: amplitude, frequency, phase, and pulse. For pulse modulation information, refer to Chapter 6, “Using Pulse Modulation (Option UNW or 320),” on page 129.
Using Analog Modulation (Option UNT) Analog Modulation Sources Figure 4-1 Analog Modulation Softkeys page 79 page 79 page 79 For details on each key, use Agilent X-Series Signal Generators User’s Guide 77
Using Analog Modulation (Option UNT) Using an Internal Modulation Source Using an Internal Modulation Source 1. Preset the signal generator. 2. Set the carrier (RF) frequency. 3. Set the RF amplitude. 4. Configure the modulation: AM ΦM FM a. Press AM a. Press FM/ΦM a. Press FM/ΦM > FM ΦM b. Set the AM type (Linear or Exponential): AM Type to highlight desired type. b. Set the deviation: FM Dev > value > frequency unit b. Set the BW (normal or high): FM ΦM to highlight desired type c.
Using Analog Modulation (Option UNT) Using an External Modulation Source Using an External Modulation Source Currently selected Default Rear panel inputs are described on page 13 AM, FM or ΦM inputs Removing a DC Offset To eliminate an offset in an externally applied FM or ΦM signal, perform a DCFM or DCΦM Calibration. NOTE You can perform this calibration for internally generated signals, but DC offset is not usually a characteristic of an internally generated signal. 1.
Using Analog Modulation (Option UNT) Using an External Modulation Source NOTE For frequencies between 9kHz and 5 MHz, Wideband AM turns off. Figure 4-2 Wideband AM Softkey Menu AM > AM Path 1 2 WB Enables and disables the wideband AM feature. Note: If the I/Q is turned off or the I/Q source is set to internal, then the wideband AM turns off. For details on each key, use key help as described on page 44. When the Wideband AM is enabled, these fields are active. Setting the Wideband AM 1.
Using Analog Modulation (Option UNT) Configuring the LF Output (Option 303) Configuring the LF Output (Option 303) The signal generator has a low frequency (LF) output. The LF output’s source can be switched between an internal modulation source or an internal function generator. Using internal modulation (Int Monitor) as the LF output source, the LF output provides a replica of the signal from the internal source that is being used to modulate the RF output.
Using Analog Modulation (Option UNT) Configuring the LF Output (Option 303) The RF On/Off hardkey does not apply to the LF OUTPUT connector. Configuring the LF Output with an Internal Modulation Source In this example, the internal FM modulation is the LF output source. See Figure 4- 3. NOTE Internal modulation (Int Monitor) is the default LF output source. Configuring the Internal Modulation as the LF Output Source 1. Press Preset. 2. Press the FM/ΦM hardkey. 3. Press FM Dev > 75 > kHz. 4.
Using Analog Modulation (Option UNT) Configuring the LF Output (Option 303) Configuring the LF Output with a Function Generator Source In this example, the function generator is the LF output source. Configuring the Function Generator as the LF Output Source 1. Press Preset. 2. Press the LF Out hardkey. 3. Press LF Out Source > Func Gen 1. Configuring the Waveform 1. Press Setup LF Out Source > LF Out Waveform > Sine. 2. Press LF Out Freq > 500 > Hz. 3. Press Return.
Using Analog Modulation (Option UNT) Configuring the LF Output (Option 303) 84 Agilent X-Series Signal Generators User’s Guide
5 Optimizing Performance Before using this information, you should be familiar with the basic operation of the signal generator. If you are not comfortable with functions such as setting the power level and frequency, refer to Chapter 3, “Basic Operation,” on page 43 and familiarize yourself with the information in that chapter.
Optimizing Performance Using the Dual Power Meter Display Using the Dual Power Meter Display The dual power meter display can be used to display the current frequency and power of either one or two power sensors. The display outputs the current frequency and power measured by the power sensors in the larger center display and in the upper right corner of the display. Refer to Figure 5- 2, Figure 5- 2, and Figure 5- 3.
Optimizing Performance Using the Dual Power Meter Display Figure 5-2 Dual Power Meter Display Menu Enables the power sensor on channel A. See page 88 Enables the power sensor on channel B. Channel B is configured similarly to channel A. See page 88 For details on each key, use key help as described on page 44.
Optimizing Performance Using the Dual Power Meter Display Figure 5-3 Configuring the Power Sensor Channels AUX Fctn > Power Meter Measurements Note: This figure illustrates channel A; channel B is similar. Enables the power meter connection type: Sockets LAN, VXI–11 LAN, or USB. Note: The VXI–11 softkey is used to communicate remotely with a power meter that has a GPIB connector via LAN–GPIB gateway. USB U2000A Series Power Sensors do not require the sensor to be calibrated.
Optimizing Performance Using the Dual Power Meter Display Example: Dual Power Meter Calibration In the following example a U2004A USB Power Sensor is connected to channel A and a N1912A P–Series Power Meter and 8482A Power Sensor are connected to channel B and are zeroed and calibrated, as required. On the signal generator: 1. Setup for Step Sweep. “Configuring a Swept Output” on page 50. CAUTION Verify RF Output power is off before continuing. 2.
Optimizing Performance Using the Dual Power Meter Display A Running Calibration(s) bar is displayed on the signal generator. Refer to Figure 5- 6 on page 90. Figure 5-6 Running Calibration(s) Bar (Zeroing Sensor) For details on each key, use key help as described on page 44. NOTE The U2000 Series USB Power Sensor, does not require a 50 MHz calibration.
Optimizing Performance Using the Dual Power Meter Display Figure 5-8 Channel A Power Sensor Displayed on MXG/EXG For details on each key, use key help as described on page 44. 6. On the N1912A P–Series Power Meter (Channel B power sensor): Connect the N1912A P–Series Power Meter to the LAN. 7. Connect the power meter sensor to channel B of the power meter. NOTE It is recommended, but not required to use the channel B on the N1912A. This provides continuity with the signal generator’s dual display.
Optimizing Performance Using the Dual Power Meter Display 13. On the signal generator: Press Channel B to On and then back to Off again. This initializes the signal generator to the external power meter. 14. Press Return > Zero Sensor A diagnostic dialog box is displayed each time an external power meter is being used and the Zero Sensor or Calibrate Sensor softkey is pressed (refer to Figure 5- 10 on page 92). Verify the power sensor is connected to the 50 MHz reference of the power meter.
Optimizing Performance Using the Dual Power Meter Display 17. Press Done Calibration progress bar is displayed. Refer to Figure 5- 12 on page 93. Figure 5-12 Running Calibration(s) Bar (Calibrating Sensor) For details on each key, use key help as described on page 44. 18. Press Return > Channel B to On 19.
Optimizing Performance Using the Power Meter Servo Using the Power Meter Servo The Power Meter Servo mode uses power meter readings to adjust the output power of the source, maintaining a constant DUT output power. The servo loop measures the output power of the DUT, compares it to the user- provided reference power, and adjusts the output of the source to achieve the user- provided power level within the settling error.
Optimizing Performance Using the Power Meter Servo Power Meter Servo Configuration The following procedure is a basic configuration for using the signal generator’s Power Meter Servo mode. CAUTION The configuration described below is one possible setup example. Consider the limits of your DUT and use caution to protect the DUT from being exposed to too much power. 1. Connect the equipment as shown in Figure 5- 15.
Optimizing Performance Using the Power Meter Servo Power Meter Continuous performs the adjustment as in Once mode, and continues to adjust the power periodically if the value differs by more than the specified Settling Error. Once these parameters are set, the servo loop engages and levels the DUT’s output power. Example The following example emphasizes the importance of setting the amplitude offset, as it protects the DUT from being exposed to too much power.
Optimizing Performance Using Flatness Correction Using Flatness Correction User flatness correction allows the digital adjustment of RF output amplitude for up to 1601 sequential linearly or arbitrarily spaced frequency points to compensate for external losses in cables, switches, or other devices.
Optimizing Performance Using Flatness Correction Figure 5-16 User Flatness Correction Softkeys For details on each key, use key help as described on page 44. Starts the user flatness calibration.
Optimizing Performance Using Flatness Correction Creating a User Flatness Correction Array In this example, you will create a user flatness correction array. The flatness correction array contains ten frequency correction pairs (amplitude correction values for each specified frequency), from 500 MHz to 1 GHz.
Optimizing Performance Using Flatness Correction Connect the Equipment • Agilent N1911A/12A or E4419A/B power metera • Agilent U2000A/01A/02A/04A power Sensora LAN/ E5810A LAN/GPIB Gateway • LAN, GPIB, or USB interface cables, as required • adapters and cables, as required GPIB Signal Generator *GPIB control of a power meter requires a LAN–GPIB gateway and use of the connection type VXI–11.
Optimizing Performance Using Flatness Correction Figure 5-17 Configure Power Meter Menu Softkeys AMPTD > More > User Flatness > Configure Power Meter Enables the power meter connection type: Sockets LAN, VXI–11 LAN, or USB. Sets the power meter’s IP address or LAN–GPIB gateway’s IP address (Sockets LAN and VXI–11 LAN only). This softkey is dependent on the selected Connection Type. Attempts to connect to the specified external power meter and execute a “*IDN?” command.
Optimizing Performance Using Flatness Correction Configure the U2000A/01A/02A/04A Power Sensor 1. Connect the power sensor to the signal generator’s front panel USB port. Refer to “Connect the Equipment” on page 100. 2. Zero the power sensor using the signal generator softkeys. CAUTION NOTE Verify the signal generator RF Output power is set to the desired amplitude before performing the power meter zero. No RF Output amplitude check is done by the signal generator during zero.
Optimizing Performance Using Flatness Correction else If Sockets LAN or VXI–11 LAN: Press Power Meter IP Address > power meter’s or LAN–GPIB gateway IP address > Enter. iii. If Sockets LAN: Press Power Meter IP Port > IP port > Enter. else If VXI–11: Press PM VXI–11 Device Name > device name > Enter. When connecting directly to the power meter, enter the device name as specified in the power meter’s documentation. Typically, this is “inst0” and is case sensitive for some power meters.
Optimizing Performance Using Flatness Correction 2. Connect the power meter to the RF output and enter the correction values: With a Power Meter Over LAN, GPIB, or USB i. Create the correction values: Manually i. Press More > User Flatness > Do Cal. The signal generator begins the user flatness calibration, and displays a progress bar. The amplitude correction values load automatically into the user flatness correction array.
Optimizing Performance Using Flatness Correction Recalling and Applying a User Flatness Correction Array The following example assumes that a user flatness correction array has been created and stored. If not, perform the Example: A 500 MHz to 1 GHz Flatness Correction Array with 10 Correction Values on page 102. 1. Preset the signal generator. 2. Recall the desired User Flatness Correction file: a. Press AMPTD > More > User Flatness > Configure Cal Array > More > Preset List > Confirm Preset. b.
Optimizing Performance Using Internal Channel Correction (N5172B/82B Only) Using Internal Channel Correction (N5172B/82B Only) NOTE There is an internal calibration routine ( Factory Calibration) that collects correction data for both the baseband and RF magnitude and phase errors over the entire RF frequency and power level range on any unit with options 653, 655, 656, and 657. The internal channel correction cannot be turned on until after the Enhanced Factory Calibration has been executed once.
Optimizing Performance Using Internal Channel Correction (N5172B/82B Only) • If active, the ACP Internal I/Q Channel Optimization filter and the Equalization filter, will be convolved with the internal channel correction filter. A hamming window is applied and the resulting filter will be truncated to 256 taps.
Optimizing Performance Using Internal Channel Correction (N5172B/82B Only) Figure 5-18 Internal Channel Correction Softkeys I/Q > More Displays a menu that controls the calibration and application of the internal baseband generator RF and baseband magnitude and phase corrections across the entire baseband bandwidth. Toggles on or off the application of the internal baseband generator RF and baseband magnitude and phase corrections across the 160MHz baseband bandwidth at the current RF frequency.
Optimizing Performance Using Internal Channel Correction (N5172B/82B Only) Configure Internal Channel Correction NOTE There is an internal calibration routine (Enhanced Factory Calibration) that collects correction data for both the baseband and RF magnitude and phase errors over the entire RF frequency and power level range on any unit with options 653, 655, 656, and 657. The internal channel correction cannot be turned on until after the Enhanced Factory Calibration has been executed once.
Optimizing Performance Using External Leveling (N5173B/83B Only) Using External Leveling (N5173B/83B Only) CAUTION While operating in external leveling mode, if either the RF or the DC connection between the signal generator and the detector is broken, maximum signal generator power can occur. This maximum power may overstress a power–sensitive device under test. Atten Hold sets to On and grays out (inactive) with Ext Detector selection.
Optimizing Performance Using External Leveling (N5173B/83B Only) External leveling lets you move the ALC feedback source closer to the device under test (DUT) so that it accounts for most of the power uncertainties inherent to the cabling and components in a test setup. Refer to Figure 5- 19. Figure 5-19 ALC Circuity Signal Generator ALC Modulator Opt 1E1 Output Attenuator (see page 113). Leveled Output RF OUTPUT Component (Amp, Filter, Atten, etc.
Optimizing Performance Using External Leveling (N5173B/83B Only) that the Ext Leveling Amptd Offset functions only while external leveling is active. For more information on using the external leveling offset feature, see “Adjusting the Signal Generator Display’s Amplitude Value” on page 117.
Optimizing Performance Using External Leveling (N5173B/83B Only) Figure 5-20 Typical Diode Detector Response at 25° C Option 1E1 Output Attenuator Behavior and Use When using the internal detector, the Option 1E1 output attenuator enables signal generator power levels down to −130 dBm at the RF Output connector. It accomplishes this by adding attenuation to the output signal after the ALC detection circuit.
Optimizing Performance Using External Leveling (N5173B/83B Only) feedback for the detection circuit has been moved beyond the output attenuator. Because the attenuator no longer affects the amplitude of the output signal, the output amplitude is determined by only the Set ALC Level softkey. With external leveling selected, the signal generator enables attenuator hold and the power range approximates the range of a standard option (no attenuator) signal generator (see the Data Sheet).
Optimizing Performance Using External Leveling (N5173B/83B Only) Recommended Equipment • Agilent 8474E negative detector • Agilent 87301D directional coupler • cables and adapters, as required Figure 5-21 Typical External Leveling Setup using a Directional Coupler Negative Detector ALC INPUT Leveled Signal RF OUTPUT Signal Generator Amplifier Coupler Configuring the Carrier 1. Press Preset. 2. Set the carrier frequency. 3.
Optimizing Performance Using External Leveling (N5173B/83B Only) With external leveling and Option 1E1, the signal generator’s power range approximates that of a standard option instrument (no Option 1E1). But Option 1E1 does let you use the attenuator to drive the ALC to its mid–power point when using amplitude values less than 0 dBm. However adding attenuation does decrease the upper range limit. For more information, see “Option 1E1 Output Attenuator Behavior and Use” on page 113. 1.
Optimizing Performance Using External Leveling (N5173B/83B Only) Adjusting the Signal Generator Display’s Amplitude Value When using external leveling, the signal generator’s displayed amplitude value will not match the leveled power of the signal at the output of the coupler/splitter. To compensate for this difference, the signal generator provides two methods for configuring the displayed power value so that it closely matches the measured value at the output of the coupler/splitter. 1.
Optimizing Performance Using Unleveled Operating Modes Using Unleveled Operating Modes Figure 5-22 Power Search and ALC Off Softkeys Auto: The calibration routine executes whenever output frequency or amplitude changes. Only available when I/Q is on. These softkeys are only active when an ARB waveforms is playing in memory. Available only when ALC = Off Span: Pressing Do Power Search executes the power search calibration routine once over a selected frequency range.
Optimizing Performance Using Unleveled Operating Modes ALC Off Mode Turning ALC off deactivates the signal generator’s automatic leveling circuitry. Turning ALC off is useful when the modulation consists of very narrow pulses that are below the pulse width specification of the ALC or when up converting external IQ signals and the modulation consists of slow amplitude variations or bursts that the automatic leveling would remove or distort.
Optimizing Performance Using Unleveled Operating Modes • Fixed – Reference level is 0.5 Vrms. This reference functions with internal, external IQ and bursted signals. This is the instrument’s default setting. • RMS – User provided reference level 0–1.414 Vrms placed in the Waveform Header. Refer to “Saving a Waveform’s Settings & Parameters” on page 155. This reference functions with internal IQ and bursted signals. • Manual – User provided reference level 0–1.414 Vrms.
Optimizing Performance Using Unleveled Operating Modes The FIXED, RMS, and MANUAL references use a DAC to apply the reference voltage and do not require the IQ signal to be present. NOTE CAUTION The MXG/EXG reference voltage is designed to operate between 0.1 Vrms to 1 Vrms nominally, but it can overrange to 1.414 Vrms. (The RMS can overrange to 1.414, if the constant values are loaded manually and all “1”s are entered for the I and Q values.
Optimizing Performance Using an Output Offset, Reference, or Multiplier Using an Output Offset, Reference, or Multiplier Setting an Output Offset Using an output offset, the signal generator can output a frequency or amplitude that is offset (positive or negative) from the entered value. RF Output = entered value − offset value Displayed Value = output frequency + offset value To set an offset: • Frequency: Press Freq > Freq Offset > offset value > frequency unit.
Optimizing Performance Using an Output Offset, Reference, or Multiplier Antenna tuned to 1321 MHz RF Amplifier Mixer IF Amplifier Filter IF = 321 MHz IF Output 321 MHz Output Frequency = 1000 MHz Selected Offset 321 MHz −679 MHz Signal Generator (local oscillator) SIgnal Generator Display 1321 MHz (Antenna Frequency) 321 MHz (IF Output) Setting an Output Reference Using an output reference, the signal generator can output a frequency or amplitude that is offset (positive or negative) by the ente
Optimizing Performance Using an Output Offset, Reference, or Multiplier Parameter Output Frequency: Example #1 Example #2 Example #3 52 MHz 48 MHz 1 GHz Comments The signal generator alerts you if the output frequency or amplitude is out of range. To set a new frequency or amplitude reference, turn the frequency reference off, and then follow the steps above.
Optimizing Performance Using an Output Offset, Reference, or Multiplier Example #1 Parameter Output Frequency: Example #2 200 MHz 200 MHz Example #3 2 GHz Comments The signal generator alerts you if the output frequency is out of range.
Optimizing Performance Using the Frequency and Phase Reference Softkeys Using the Frequency and Phase Reference Softkeys The MXG/EXG can be set to have either a user- determined frequency or phase reference. Figure 5-25 Frequency Reference and Frequency Offset Softkeys Using Free Run, Step Dwell, and Timer Trigger Free Run, Step Dwell (time), and Timer Trigger can be used to adjust the time spent at any point in a Step Sweep or a List Sweep.
Optimizing Performance Using Free Run, Step Dwell, and Timer Trigger depending on options) plus the minimum settled time that is needed to make the measurement. If the measurement requires external equipment synchronization, consider using hardware triggers. Figure 5-26 Free Run, Set Dwell, and Timer Trigger Softkeys Sweep > Configure Step Sweep > More Use Step Dwell with Free Run when additional measurement wait time is desired after settling.
Optimizing Performance Using a USB Keyboard Using a USB Keyboard You can use a USB keyboard to remotely control the RF output state, the modulation state, and to select a memory sequence and register. The register selection, RF output state, and modulation state are affected by power cycle or preset, but the USB keyboard control state and the sequence selection are not.
6 Using Pulse Modulation (Option UNW or 320) Before using this information, you should be familiar with the basic operation of the signal generator. If you are not comfortable with functions such as setting the power level and frequency, refer to Chapter 3, “Basic Operation,” on page 43 and familiarize yourself with the information in that chapter.
Using Pulse Modulation (Option UNW or 320) Figure 6-1 Pulse Softkeys Note: Pulse Period and Pulse Width are not available when Pulse Train is selected as the Pulse Source. page 133 page 133 page 135 These softkeys are only available when the Pulse–Source is set to Adjustable Doublet. Determines how the signal generator responds to an external pulse signal. Normal = high state. TTL signal Invert = low state. Low = settled Latency from the external pulse input to the pulse sync output ≈ 50−60 ns.
Using Pulse Modulation (Option UNW or 320) Pulse Characteristics Pulse Characteristics NOTE When using very narrow pulses that are below the signal generator’s ALC pulse width specification, or leveled pulses with an unusually long duty cycle, it is often useful to turn ALC off (see page 119). Pulse Source Perioda Type Square Internal free run pulse train with 50% duty cycle.
Using Pulse Modulation (Option UNW or 320) Pulse Characteristics Rear panel inputs are described on page 13 External pulse input Figure 6-2 Adjustable Doublet External Trigger RF Output Pulse 1 Pulse 1 Delay Width The delay of the first pulse is measured from the leading edge of the external trigger signal. Pulse 2 Delay Pulse 2 Width The delay of the second pulse is measured from the leading edge of the first pulse.
Using Pulse Modulation (Option UNW or 320) The Basic Procedure The Basic Procedure 1. Preset the signal generator. 2. Set the carrier (RF) frequency. 3. Set the RF amplitude. 4. Configure the modulation: a. Set the pulse source: Press Pulse > Pulse Source > selection b.
Using Pulse Modulation (Option UNW or 320) Example 4. Set the pulse period to 100 microseconds: Press Pulse > Pulse Period > 100 > usec. 5. Set the pulse width to 24 microseconds: Press Pulse > Pulse Width > 24 > usec 6. Turn on both the pulse modulation and the RF output. The PULSE annunciator displays and the RF output LED lights. If the modulation does not seem to be working properly, refer to “No Modulation at the RF Output” on page 382.
Using Pulse Modulation (Option UNW or 320) Pulse Train (Option 320 – Requires: Option UNW) Pulse Train (Option 320 – Requires: Option UNW) The Option 320 Pulse Train feature enables the specification of up to 2047 independent pulse cycles, each of which has an “On Time”, during which the RF output is measurable at the RF output connector, and an "Off Time", during which the RF output is attenuated.
Using Pulse Modulation (Option UNW or 320) Pulse Train (Option 320 – Requires: Option UNW) Figure 6-5 Edit Pulse Train Menu Softkeys For details on each key, use key help as described on page 44. These softkeys provide ease of use in changing the pulse cycle settings in the pulse train. Pulse > Pulse Source > More > Pulse Train > Edit Pulse Train page 137 This column indicates the row of a each pulse train cycle.
Using Pulse Modulation (Option UNW or 320) Pulse Train (Option 320 – Requires: Option UNW) Figure 6-6 Display Pulse Train Menu Softkeys Pulse > Pulse Source > More > Pulse Train > Edit Pulse Train > Display Pulse Train This softkey shifts the time offset from the left hand side of the display to the one specified. Increments and decrements are 1/20th of the visible pulse train. Use these softkeys to optimize the view of the different characteristics of the pulse train.
Using Pulse Modulation (Option UNW or 320) Pulse Train (Option 320 – Requires: Option UNW) Figure 6-7 Pulse Train: Import From Selected File Softkeys For details on each key, use key help as described on page 44. Pulse > Pulse Source > More > Pulse Train > Edit Pulse Train > More page 65 These softkeys delete individual On Time or Off Time elements as well as the Repeat cycle counts. Deleting all Pulse Cycle rows (elements) must be confirmed.
Using Pulse Modulation (Option UNW or 320) Pulse Train (Option 320 – Requires: Option UNW) Figure 6-8 Pulse Train: Export to File Softkeys Pulse > Pulse Source > More > Pulse Train > Edit Pulse Train > More Note: Files can be FTP’d to the BIN (Binary) folder in the instrument, or a USB stick can be used to download the files to the instrument. Refer to page 66. page 138 Selects whether the decimal point is a “.” or “, “ ” during export of the CSV/ASCII files.
Using Pulse Modulation (Option UNW or 320) Pulse Train (Option 320 – Requires: Option UNW) 140 Agilent X-Series Signal Generators User’s Guide
7 Basic Digital Operation—No BBG Option Installed Before using this information, you should be familiar with the basic operation of the signal generator. If you are not comfortable with functions such as setting power level and frequency, refer to Chapter 3, “Basic Operation,” on page 43 and familiarize yourself with the information in that chapter. See also “Adding Real–Time Noise to a Dual ARB Waveform” on page 245.
Basic Digital Operation—No BBG Option Installed I/Q Modulation I/Q Modulation The following factors contribute to the error vector magnitude: • Differences in amplitude, phase, and delay between the I and Q channels • DC offsets The I/Q menu provides adjustments and calibration to compensate for some of the differences in the I and Q signals or to add impairments. See I/Q Modulation on page 204 for additional information. See also “Modulating the Carrier Signal” on page 59.
Basic Digital Operation—No BBG Option Installed I/Q Modulation The following table shows common uses for the adjustments. Table 7-1 I/Q Adjustments Uses I/Q Adjustment Effect Impairment Offset Carrier Feedthrough dc offset EVM error phase skew I/Q Images I/Q path delay Quadrature Angle Configuring the Front Panel Inputs The MXG/EXG accepts externally supplied analog I and Q signals through the front panel I Input and Q Input for modulating onto the carrier. 1.
Basic Digital Operation—No BBG Option Installed I/Q Modulation 144 Agilent X-Series Signal Generators User’s Guide
8 Basic Digital Operation (Option 653/655/656/657) Before using this information, you should be familiar with the basic operation of the signal generator. If you are not comfortable with functions such as setting power level and frequency, refer to Chapter 3, “Basic Operation,” on page 43 and familiarize yourself with the information in that chapter. The features described in this chapter are available only in vector signal generators with Option 653 or 655 (N5172B) or Option 656 or 657 (N5182B).
Basic Digital Operation (Option 653/655/656/657) Waveform File Basics Waveform File Basics There are two types of waveform files: • A segment is a waveform file that you download to the signal generator. For information on creating and downloading waveform files, refer to the Programming Guide. • A sequence is a file you create in the signal generator that contains pointers to one or more waveform files (segments, other sequences, or both). For information on creating sequences, see page 151.
Basic Digital Operation (Option 653/655/656/657) Waveform File Basics Figure 8-1 Dual ARB Softkeys If you set the ARB sample clock when the dual ARB is off, the new setting is applied when the dual ARB player is turned on; this setting survives toggling the Dual ARB player off and on. page 245 page 148 page 194 page 194 page 178 These softkeys are only available in the Dual ARB’s Arb Setup menu. page 200 page 151 page 203 page 225 page 225 Note: This is second of two Arb menus.
Basic Digital Operation (Option 653/655/656/657) Storing, Loading, and Playing a Waveform Segment Storing, Loading, and Playing a Waveform Segment NOTE The MXG/EXG’s ARB Waveform File Cache is limited to 128 files. Consequently, once the 128 file cache limit has been reached, the waveform switching speed will be much slower for additional files loaded into the volatile waveform memory (BBG). Before using this information, you should be familiar with the signal generator’s file menus.
Basic Digital Operation (Option 653/655/656/657) Storing, Loading, and Playing a Waveform Segment 2. Press Load Store to highlight Load, then use the arrow keys to highlight the desired waveform segment. 3. If there is already a copy of this segment in the currently selected media and you do not want to overwrite it, rename the waveform segment before you load it (refer to the previous procedure). 4. Press Load Segment From currently selected Media.
Basic Digital Operation (Option 653/655/656/657) Storing, Loading, and Playing a Waveform Segment Annunciators display with active waveform (ARB On) Current waveform selection 5. Configure the RF Output: Set the RF carrier frequency and amplitude, and turn on the RF output. The waveform segment is now available at the signal generator’s RF Output connector.
Basic Digital Operation (Option 653/655/656/657) Waveform Sequences Waveform Sequences Figure 8-3 Waveform Sequence Softkeys Mode > Dual ARB To display this softkey, select a waveform sequence. Sequence name Sequence contents see page 174 For details on each key, use key help as described on page 44. A waveform sequence is a file that contains pointers to one or more waveform segments or other waveform sequences, or both.
Basic Digital Operation (Option 653/655/656/657) Waveform Sequences Creating a Sequence A waveform sequence can contain up to 1,024 segments and have both segments and other sequences (nested sequences). The signal generator lets you set the number of times the segments and nested sequences repeat during play back. But there is a difference between repeating a segment versus repeating a nested sequence.
Basic Digital Operation (Option 653/655/656/657) Waveform Sequences 3. Name and store the waveform sequence to the Seq file catalog: a. Press More > Name and Store. b. Enter a file name and press Enter. See also, “Viewing the Contents of a Sequence” on page 153 and “Setting Marker Points in a Waveform Segment” on page 168. Viewing the Contents of a Sequence There are two ways to view the contents of a waveform sequence: Through the Waveform Sequences Softkey 1.
Basic Digital Operation (Option 653/655/656/657) Waveform Sequences 2. Change the first segment so that it repeats 100 times: Highlight the first segment entry and press Edit Repetitions > 100 > Enter. The cursor moves to the next entry. 3. Change the repetition for the selected entry to 200: Press Edit Repetitions > 200 > Enter. 4. Save the changes made in the previous steps: Press More > Name and Store > Enter. To save the changes as a new sequence: a. Press More > Name and Store > Clear Text. b.
Basic Digital Operation (Option 653/655/656/657) Saving a Waveform’s Settings & Parameters 2. Generate the waveform: Press ARB Off On to On. This plays the selected waveform sequence. During the waveform sequence generation, both the I/Q and ARB annunciators turn on, and the waveform modulates the RF carrier. 3. Configure the RF output: a. Set the RF carrier frequency. b. Set the RF output amplitude. c. Turn on the RF output.
Basic Digital Operation (Option 653/655/656/657) Saving a Waveform’s Settings & Parameters All settings in this menu can be stored to the file header (Table 8-1 on page 156 lists all settings stored in a file header) Softkey label, file header setting The Runtime Scaling softkey is only available under the Dual ARB menu.
Basic Digital Operation (Option 653/655/656/657) Saving a Waveform’s Settings & Parameters Table 8-1 File Header Entries (Continued) RF Blank Routing Which marker, if any, implements the RF blanking function (described on page 172) when the marker signal is low. RF blanking also uses ALC hold. There is no need to select the ALC Hold Routing for the same marker when you are using the RF Blank Routing function. When the marker signal goes high, RF blanking discontinues.
Basic Digital Operation (Option 653/655/656/657) Saving a Waveform’s Settings & Parameters The Current Inst. Settings column shows the current signal generator settings. In this example, these are the settings that you will save to the file header. NOTE If a setting is unspecified in the file header, the signal generator uses its current value for that setting when you select and play the waveform. Figure 8-5 Example File Header Mode > Dual ARB > More > Header Utilities The name of the waveform file.
Basic Digital Operation (Option 653/655/656/657) Saving a Waveform’s Settings & Parameters d. Return to the Header Utilities menu: Press Return > More > Header Utilities. As shown in the following figure, the Current Inst. Settings column now reflects the changes to the current signal generator setup, but the saved header values have not changed. Values differ between the two columns e. Save the current settings to the file header: Press the Save Setup To Header softkey.
Basic Digital Operation (Option 653/655/656/657) Saving a Waveform’s Settings & Parameters Active catalog Active media Active waveform catalog Type: WFM1 = Volatile Segment NVWFM = Non–Volatile Segment SEQ = Sequence Catalogs that enable you to view files in the active media. For details on selecting the active media, see page 63. Files in BBG media For details on each key, use key help as described on page 44. 2. If the desired catalog is not displayed, select it. 3.
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers Using Waveform Markers The signal generator provides four waveform markers to mark specific points on a waveform segment. When the signal generator encounters an enabled marker, an auxiliary signal is routed to a rear panel event output that corresponds to the marker number. • Event 1 is available at both the EVENT 1 BNC connector (see page 17), and a pin on the AUXILIARY I/O connector (see page 18).
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers Waveform Marker Concepts The signal generator’s Dual ARB provides four waveform markers for use on a waveform segment. You can set each marker’s polarity and marker points (on a single sample point or over a range of sample points). Each marker can also perform ALC hold, or RF Blanking and ALC hold.
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers ALC Hold Marker Function While you can set a marker function (described as Marker Routing on the softkey label) either before or after you set marker points (page 168), setting a marker function before setting marker points may cause power spikes or loss of power at the RF output.
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers Example of Correct Use Waveform: 1022 points Marker range: 95–97 Marker polarity: Positive This example shows a marker set to sample the waveform’s area of highest amplitude. Note that the marker is set well before the waveform’s area of lowest amplitude. This takes into account any response difference between the marker and the waveform signal.
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers Example of Incorrect Use Waveform: 1022 points Marker range: 110–1022 Marker polarity: Negative This figure shows that a negative polarity marker goes low during the marker on points; the marker signal goes high during the off points. The ALC samples the waveform during the off marker points.
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers Accessing Marker Utilities For details on each key, use key help as described on page 44. Mode > Dual ARB > More > Marker Utilities The settings in these menus can be stored to the file header, see page 155. Note: This is the second Arb menu.
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers Viewing Waveform Segment Markers Markers are applied to waveform segments. Use the following steps to view the markers set for a segment (this example uses the factory–supplied segment, SINE_TEST_WFM). 1. In the second Arb menu (page 166), press Marker Utilities > Set Markers. 2. Highlight the desired waveform segment (in this example, SINE_TEST_WFM). 3. Press Display Waveform and Markers > Zoom in Max.
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers Press Last Mkr Point > 17 > Enter > Apply To Waveform > Return. This turns off all marker points for the active marker within the range set in Steps 2 and 3, as shown at right. How to view markers is described on page 167. Clearing a Single Marker Point Use the steps described in “Clearing a Range of Marker Points” on page 167, but set both the first and last marker point to the value of the point you want to clear.
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers Placing a Marker on a Single Point On the First Point 1. In the second Arb menu (page 166), press Marker Utilities > Set Markers. 2. Highlight the desired waveform segment. 3. Select the desired marker number: Press Marker 1 2 3 4. 4. Press Set Marker On First Point. This sets a marker on the first point in the segment for the marker number selected in Step 3.
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers This causes the marker to occur on every other point (one sample point is skipped) within the marker point range, as shown at right. How to view markers is described on page 167. One application of the skipped point feature is the creation of a clock signal as the EVENT output.
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers Viewing a Marker Pulse When a waveform plays (page 154), you can detect a set and enabled marker’s pulse at the rear panel event connector/Aux I/O pin that corresponds to that marker number. This example demonstrates how to view a marker pulse generated by a waveform segment that has at least one marker point set (page 168). The process is the same for a waveform sequence.
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers Using the RF Blanking Marker Function While you can set a marker function (described as Marker Routing on the softkey label in the Marker Utilities menu) either before or after setting the marker points (page 168), setting a marker function before you set marker points may change the RF output. RF Blanking includes ALC hold (described on page 163, note Caution regarding unleveled power).
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers RFSignal Signal RF Marker Polarity = Positive When marker polarity is positive (the default setting), the RF output is blanked during the off marker points. ≈3.3V 0V Marker Point 1 Segment 180 200 RFSignal Signal RF Marker Polarity = Negative When marker polarity is negative, the RF output is blanked during the on marker points ≈3.
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers Setting Marker Polarity Setting a negative marker polarity inverts the marker signal. 1. In second Arb menu (page 166), press Marker Utilities > Marker Polarity. 2. For each marker, set the marker polarity as desired. • The default marker polarity is positive. • Each marker polarity is set independently. See also, “Saving Marker Polarity and Routing Settings” on page 162.
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers Figure 8-6 Waveform Sequence Menus for Enabling/Disabling Segment Markers Mode > Dual ARB > More Note: This is the second Arb menu. Enable/Disable markers while creating a waveform sequence For details on each key, use key help as described on page 44.
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers Enabling and Disabling Markers in a Waveform Sequence Select the waveform segments within a waveform sequence to enable or disable each segment’s markers independently. You can enable or disable the markers either at the time of creating the sequence or after the sequence has been created and stored. If the sequence has already been stored, you must store the sequence again after making any changes.
Basic Digital Operation (Option 653/655/656/657) Using Waveform Markers Using the EVENT Output Signal as an Instrument Trigger For details on each key, use key help as described on page 44. One of the uses for the EVENT output signal (marker signal) is to trigger a measurement instrument. You can set up the markers to start the measurement at the beginning of the waveform, at any single point in the waveform, or on multiple points in the waveform.
Basic Digital Operation (Option 653/655/656/657) Triggering a Waveform Triggering a Waveform Figure 8-7 Triggering Softkeys Mode > Dual ARB page 179 page 180 For details on each key, use key help as described on page 44. Triggers control data transmission by controlling when the signal generator transmits the modulating signal.
Basic Digital Operation (Option 653/655/656/657) Triggering a Waveform Trigger Type Type defines the trigger mode: how the waveform plays when triggered. NOTE The example below shows Dual ARB Mode, but trigger functionality is similar for other modulation modes. Available trigger types vary depending on the modulation mode selected. Mode > Dual ARB > Trigger Type Immediately triggers and plays the waveform; triggers received while the waveform is playing are ignored.
Basic Digital Operation (Option 653/655/656/657) Triggering a Waveform • Segment Advance mode plays a segment in a sequence only if triggered. The trigger source controls segment–to–segment playing (see Example: Segment Advance Triggering on page 181). A trigger received during the last segment loops play to the first segment in the sequence.
Basic Digital Operation (Option 653/655/656/657) Triggering a Waveform Example: Segment Advance Triggering Segment advance triggering enables you to control the segment playback within a waveform sequence. This type of triggering ignores the repetition value (page 153). For example if a segment has repetition value of 50 and you select Single as the segment advance triggering mode, the segment still plays only once. The following example uses a waveform sequence that has two segments.
Basic Digital Operation (Option 653/655/656/657) Triggering a Waveform Example: Gated Triggering Gated triggering enables you to define the on and off states of a modulating waveform. 1. Connect the output of a function generator to the signal generator’s rear panel PAT TRIG IN connector, as shown in the following figure. This connection is applicable to all external triggering methods. The optional oscilloscope connection enables you to see the effect that the trigger signal has on the RF output. 2.
Basic Digital Operation (Option 653/655/656/657) Triggering a Waveform 7. On the function generator, configure a TTL signal for the external gating trigger. 8. (Optional) Monitor the waveform: Configure the oscilloscope to display both the output of the signal generator, and the external triggering signal. You will see the waveform modulating the output during the gate active periods (low in this example). The following figure shows an example display.
Basic Digital Operation (Option 653/655/656/657) Triggering a Waveform Example: External Triggering Use the following example to set the signal generator to output a modulated RF signal 100 milliseconds after a change in TTL state from low to high occurs at the PATT TRIG IN rear panel BNC connector 1. Connect the signal generator to the function generator as shown above. 2. Configure the RF output: • Set the desired frequency. • Set the desired amplitude. • Turn on the RF output. 3.
Basic Digital Operation (Option 653/655/656/657) Clipping a Waveform Clipping a Waveform Digitally modulated signals with high power peaks can cause intermodulation distortion, resulting in spectral regrowth that can interfere with signals in adjacent frequency bands. The clipping function enables you to reduce high power peaks by clipping the I and Q data to a selected percentage of its highest peak, thereby reducing spectral regrowth.
Basic Digital Operation (Option 653/655/656/657) Clipping a Waveform How Power Peaks Develop To see how clipping reduces high power peaks, it is important to understand how the peaks develop as you construct a signal. Multiple Channel Summing I/Q waveforms can be the summation of multiple channels, as shown in the following figure.
Basic Digital Operation (Option 653/655/656/657) Clipping a Waveform Combining the I and Q Waveforms When the I and Q waveforms combine in the I/Q modulator to create an RF waveform, the magnitude of the RF envelope is , where the squaring of I and Q always results in a positive value. As shown in the following figure, simultaneous positive and negative peaks in the I and Q waveforms do not cancel each other, but combine to create an even greater peak.
Basic Digital Operation (Option 653/655/656/657) Clipping a Waveform How Peaks Cause Spectral Regrowth In a waveform, high power peaks that occur infrequently cause the waveform to have a high peak–to–average power ratio, as illustrated in the following figure. Because the gain of a transmitter’s power amplifier is set to provide a specific average power, high peaks can cause the power amplifier to move toward saturation. This causes the intermodulation distortion that generates spectral regrowth.
Basic Digital Operation (Option 653/655/656/657) Clipping a Waveform How Clipping Reduces Peak–to–Average Power You can reduce peak–to–average power, and consequently spectral regrowth, by clipping the waveform. Clipping limits waveform power peaks by clipping the I and Q data to a selected percentage of its highest peak. The Signal Generator provides two methods of clipping: • Circular clipping is applied to the composite I/Q data (I and Q data are equally clipped).
Basic Digital Operation (Option 653/655/656/657) Clipping a Waveform Figure 8-10 Rectangular Clipping 190 Agilent X-Series Signal Generators User’s Guide
Basic Digital Operation (Option 653/655/656/657) Clipping a Waveform Figure 8-11 Reduction of Peak–to–Average Power Agilent X-Series Signal Generators User’s Guide 191
Basic Digital Operation (Option 653/655/656/657) Clipping a Waveform Configuring Circular Clipping Use this example to configure circular clipping and observe its affect on the peak–to–average power ratio of a waveform. Circular clipping clips the composite I/Q data (I and Q data are clipped equally). For more information about circular clipping, refer to “How Clipping Reduces Peak–to–Average Power” on page 189. CAUTION Clipping is non–reversible and cumulative.
Basic Digital Operation (Option 653/655/656/657) Clipping a Waveform Configuring Rectangular Clipping Use this example to configure rectangular clipping. Rectangular clipping clips the I and Q data independently. For more information about rectangular clipping, refer to “How Clipping Reduces Peak–to–Average Power” on page 189. CAUTION Clipping is non–reversible and cumulative. Save a copy of the waveform file before you apply clipping. Copy a Waveform File 1.
Basic Digital Operation (Option 653/655/656/657) Scaling a Waveform Scaling a Waveform The signal generator uses an interpolation algorithm (sampling between the I/Q data points) when reconstructing a waveform. For common waveforms, this interpolation can cause overshoots, which may create a DAC over–range error condition. This chapter describes how DAC over–range errors occur and how you can use waveform scaling to eliminate these errors.
Basic Digital Operation (Option 653/655/656/657) Scaling a Waveform How DAC Over–Range Errors Occur The signal generator uses an interpolator filter when it converts digital I and Q baseband waveforms to analog waveforms. Because the clock rate of the interpolator is four times that of the baseband clock, the interpolator calculates sample points between the incoming baseband samples and smooths the waveform as shown in the figure at the right.
Basic Digital Operation (Option 653/655/656/657) Scaling a Waveform How Scaling Eliminates DAC Over–Range Errors Scaling reduces the amplitude of the baseband waveform while maintaining its basic shape and characteristics, such as peak–to–average power ratio.
Basic Digital Operation (Option 653/655/656/657) Scaling a Waveform Setting Waveform Runtime Scaling Runtime scaling scales the waveform data during playback; it does not affect the stored data. You can apply runtime scaling to either a segment or sequence, and set the scaling value either while the ARB is on or off. This type of scaling is well suited for eliminating DAC over–range errors.
Basic Digital Operation (Option 653/655/656/657) Scaling a Waveform Setting Waveform Scaling Waveform scaling differs from waveform runtime scaling in that it permanently affects waveform data and only applies to waveform segments stored in BBG media. You scale the waveform either up or down as a percentage of the DAC full scale (100%). If you scale your waveforms using this method, you may also need to change the waveform runtime scaling value to accommodate this scaling.
Basic Digital Operation (Option 653/655/656/657) Scaling a Waveform Apply Scaling to the Copied Waveform File CAUTION This type of scaling is non–reversible. Any data lost in the scaling operation cannot be restored. Save a copy of the waveform file before scaling. 1. Open the DUAL ARB Waveform Utilities menu: Press Mode > Dual ARB > More > Waveform Utilities. 2. In the list of BBG Media segment files, highlight the copied file (in this example, MY_TEST_SCAL). 3.
Basic Digital Operation (Option 653/655/656/657) Setting the Baseband Frequency Offset Setting the Baseband Frequency Offset The baseband frequency offset specifies a value to shift the baseband frequency up to ±50 MHz within the BBG 100 MHz signal bandwidth, depending on the signal generator’s baseband generator option.
Basic Digital Operation (Option 653/655/656/657) Setting the Baseband Frequency Offset NOTE Changing the baseband frequency offset may cause a DAC over range condition that generates error 628, Baseband Generator DAC over range. The signal generator incorporates an automatic scaling feature to minimize this occurrence. For more information, see “DAC Over–Range Conditions and Scaling” on page 202.
Basic Digital Operation (Option 653/655/656/657) Setting the Baseband Frequency Offset Modulated carrier with 0 Hz baseband frequency offset Modulated carrier with 20 MHz baseband frequency offset Modulated RF signal LO/carrier feedthrough Spectrum analyzer set to a span of 100 MHz DAC Over–Range Conditions and Scaling When using the baseband frequency offset (at a setting other than 0 Hz), it is possible to create a DAC over–range condition, which causes the Agilent MXG/EXG to generate an error.
Basic Digital Operation (Option 653/655/656/657) Setting the Baseband Frequency Offset Figure 8-14 Dual ARB DAC Over–Range Protection Softkey Location When the DAC over–range protection is off, eliminate over–range conditions by decreasing the scaling value (see “Setting Waveform Runtime Scaling” on page 197). For details on each key, use key help as described on page 44. page 226 Default setting is On.
Basic Digital Operation (Option 653/655/656/657) I/Q Modulation I/Q Modulation The following factors contribute to the error vector magnitude: • Differences in amplitude, phase, and delay between the I and Q channels • DC offsets The I/Q menu not only enables you to select the I/Q signal source and output, it also provides adjustments and calibrations to compensate for differences in the I and Q signals. See also, “Modulating the Carrier Signal” on page 59.
Basic Digital Operation (Option 653/655/656/657) I/Q Modulation Figure 8-15 I/Q Display and Softkeys This panel displays the current settings for the I/Q signal routing and I/Q correction optimized path. This panel displays the current status and settings of the I/Q adjustments. Use the Page Up and Page Down keys to scroll through these parameters. Grey indicates an inactive (off) adjustment. page 208 These selections are reflected in the I/Q Routing & Optimization graphic.
Basic Digital Operation (Option 653/655/656/657) I/Q Modulation Using the Rear Panel I and Q Outputs NOTE The rear panel I and Q connectors only output a signal while using the internal BBG. In addition to modulating the carrier, the signal generator also routes the internally generated I and Q signals to the rear panel I and Q connectors. These output signals are post DAC, so they are in analog form.
Basic Digital Operation (Option 653/655/656/657) I/Q Modulation Configuring the Front Panel Inputs The signal generator accepts externally supplied analog I and Q signals through the front panel I Input and Q Input. You can use the external signals as the modulating source, or sum the external signals with the internal baseband generator signals. 1. Connect I and Q signals to the front panel connectors. a. Connect an analog I signal to the signal generator’s front panel I Input. b.
Basic Digital Operation (Option 653/655/656/657) I/Q Adjustments I/Q Adjustments Use the I/Q Adjustments to compensate for or add impairments to the I/Q signal. Adjusts the I signal amplitude relative to the Q signal amplitude. Use this as an internal impairment, or to compensate for differences in signal path loss that occur due to path irregularities in the external I and Q output cabling. The DC offset values are calibrated relative to the RMS waveform voltage being played out of the ARB. See page 158.
Basic Digital Operation (Option 653/655/656/657) I/Q Adjustments Table 8-2 I/Q Adjustments Uses I/Q Adjustment Effect Impairment Offset Carrier feedthrough dc offset EVM error phase skew I/Q images I/Q path delay I/Q Skew EVM error high sample rate phase skew or I/Q path delay I/Q Gain Balance I/Q amplitude difference I/Q gain ratio I/Q Phase I/Q phase rotation RF phase adjustment Quadrature Angle The I/Q adjustment, I/Q Delay, is not for adding impairments; its function is to compensat
Basic Digital Operation (Option 653/655/656/657) I/Q Calibration I/Q Calibration Use the I/Q calibration for I and Q signal corrections. What aspects of the I and Q signal is corrected depends on whether the signal is internally or externally generated. Correction Internal I and Q External I and Q Offset X X Gain Balance X X Quadrature Error X X When you perform an I/Q calibration, that calibration data takes precedence over the factory–supplied calibration data.
Basic Digital Operation (Option 653/655/656/657) I/Q Calibration DC optimizes the I/Q performance for the current instrument settings, and typically completes in several seconds.
Basic Digital Operation (Option 653/655/656/657) Using the Equalization Filter Using the Equalization Filter An equalization FIR file can be created externally, uploaded via SCPI, and subsequently selected from the file system (refer to “Working with Files” on page 61). For information related to downloading FIR file coefficients, refer to the Programming Guide. For information regarding working with FIR file coefficients manually, refer to “Modifying a FIR Filter Using the FIR Table Editor” on page 220.
Basic Digital Operation (Option 653/655/656/657) Using the Equalization Filter Figure 8-16 Int Equalization Filter Softkeys For details on each key, use key help as described on page 44. I/Q > More Enables the internal equalization filter. Opens a file catalog of FIR filters to select as the equalization filter. Equalization filters are typically complex and must have an oversample ratio of 1. The filter must not have more than 256 taps (512 coefficients for a complex filter).
Basic Digital Operation (Option 653/655/656/657) Using Finite Impulse Response (FIR) Filters in the Dual ARB Real-Time Modulation Filter Using Finite Impulse Response (FIR) Filters in the Dual ARB Real-Time Modulation Filter Finite Impulse Response filters can be used to compress single carrier I/Q waveforms down to just the I/Q constellation points and then define the transitions similar to the modulation filter in Arb Custom (refer to “Using Finite Impulse Response (FIR) Filters with Custom Modulation” o
Basic Digital Operation (Option 653/655/656/657) Using Finite Impulse Response (FIR) Filters in the Dual ARB Real-Time Modulation Filter Creating a User–Defined FIR Filter Using the FIR Table Editor In this procedure, you use the FIR Values table editor to create and store an 8–symbol, windowed sync function filter with an oversample ratio of 4. Accessing the Table Editor 1. Press Preset. 2. Press Mode > Dual ARB > Arb Setup > More > Real-Time Modulation Filter > Select > Nyquist. 3. Press Define User FIR.
Basic Digital Operation (Option 653/655/656/657) Using Finite Impulse Response (FIR) Filters in the Dual ARB Real-Time Modulation Filter 3. Use the numeric keypad to type the first value (−0.000076) from Table 8- 3. As you press the numeric keys, the numbers are displayed in the active entry area. (If you make a mistake, you can correct it using the backspace key.) 4. Continue entering the coefficient values from the table in step 1 until all 16 values have been entered.
Basic Digital Operation (Option 653/655/656/657) Using Finite Impulse Response (FIR) Filters in the Dual ARB Real-Time Modulation Filter Duplicating the First 16 Coefficients Using Mirror Table In a windowed sinc function filter, the second half of the coefficients are identical to the first half in reverse order. The signal generator provides a mirror table function that automatically duplicates the existing coefficient values in the reverse order. 1. Press Mirror Table.
Basic Digital Operation (Option 653/655/656/657) Using Finite Impulse Response (FIR) Filters in the Dual ARB Real-Time Modulation Filter Setting the Oversample Ratio NOTE Modulation filters are real and have an oversample ratio (OSR) of two or greater. Equalization filters are typically complex and must have an OSR of one (refer to “Using the Equalization Filter” on page 212 and to “Setting the Real- Time Modulation Filter” on page 224).
Basic Digital Operation (Option 653/655/656/657) Using Finite Impulse Response (FIR) Filters in the Dual ARB Real-Time Modulation Filter Figure 8-20 For details on each key, use key help as described on page 44. 2. Press Return. 3. Press Display Impulse Response. Refer to Figure 8- 21. Figure 8-21 For details on each key, use key help as described on page 44. 4. Press Return to return to the menu keys. Storing the Filter to Memory Use the following steps to store the file. 1.
Basic Digital Operation (Option 653/655/656/657) Modifying a FIR Filter Using the FIR Table Editor Figure 8-22 These keys manage the table of DMOD files in internal storage. Catalog displays FIR files that have been previously saved by the user. For details on each key, use key help as described on page 44. Memory is also shared by instrument state files and list sweep files. This filter can now be used to customize a modulation format or it can be used as a basis for a new filter design.
Basic Digital Operation (Option 653/655/656/657) Modifying a FIR Filter Using the FIR Table Editor Loading the Default Gaussian FIR File Figure 8-23 Loading the Default Gaussian FIR File Mode > Dual ARB > Arb Setup > More > Real-Time Modulation Filter For details on each key, use key help as described on page 44. These softkeys select a window function (apodization function) for a filter. 1. Press Preset. 2.
Basic Digital Operation (Option 653/655/656/657) Modifying a FIR Filter Using the FIR Table Editor Figure 8-24 For details on each key, use key help as described on page 44. 7. Press Return. Modifying the Coefficients 1. Using the front panel arrow keys, highlight coefficient 15. 2. Press 0 > Enter. 3. Press Display Impulse Response. Figure 8-25 For details on each key, use key help as described on page 44. Refer to Figure 8- 25.
Basic Digital Operation (Option 653/655/656/657) Modifying a FIR Filter Using the FIR Table Editor Storing the Filter to Memory The maximum file name length is 23 characters (alphanumeric and special characters). 1. Press Return > Return > Load/Store > Store To File. 2. Name the file NEWFIR2. 3. Press Enter. The contents of the current FIR table editor are stored to a file in non–volatile memory and the catalog of FIR files is updated to show the new file.
Basic Digital Operation (Option 653/655/656/657) Setting the Real-Time Modulation Filter Setting the Real-Time Modulation Filter The real- time modulation filter effectively compresses a single carrier I/Q waveform down to just the I/Q constellation points and then controls the transitions similar to the modulation filter in Arb Custom modulation. The key difference is that this filter is applied as the waveform plays, rather than in the waveform data itself.
Basic Digital Operation (Option 653/655/656/657) Multiple Baseband Generator Synchronization Common uses for the real- time modulation feature include: • Where the single carrier rectangular ideal I/Q symbol decision points are known and are to have an over- sampled filter applied. • Where greater effective MXG/EXG memory size is required. • When you have a low rate waveform that could benefit from a higher OSR that does not make the waveform longer.
Basic Digital Operation (Option 653/655/656/657) Multiple Baseband Generator Synchronization Figure 8-27 Multiple Baseband Generator Synchronization (BBG Synchronization) Trigger Softkeys and Menu Location Note: The BBG sync feature automatically configures the trigger settings shown below. To avoid a settings conflict error in this process, manually configure the trigger settings prior to setting the BBG sync parameters shown on page 227.
Basic Digital Operation (Option 653/655/656/657) Multiple Baseband Generator Synchronization Figure 8-28 Multiple BBG Synchronization Front Panel Displays Mode > Dual ARB > Arb Setup > More > Multi-BBG Sync Setup Master Display and Available Softkeys Select Off, Master, or Slave This is a persistent setting that survives both preset and cycling the power. Grayed–out on master, active for slaves. Synchronizes the baseband generators for all instruments in the system.
Basic Digital Operation (Option 653/655/656/657) Multiple Baseband Generator Synchronization Understanding the Master/Slave System System Delay The multiple BBG synchronization feature provides a system for synchronizing the waveform generation capability of up to 16 signal generators to within a characteristic value of ± 8 ns between the master and the last slave. This minor amount of delay (± 8 ns) can be reduced further to picosecond resolution by using the I/Q Delay softkey located in the I/Q menu.
Basic Digital Operation (Option 653/655/656/657) Multiple Baseband Generator Synchronization generation, appropriately configure the trigger settings prior to selecting a signal generator as the master or slave. The system trigger propagates in the same manner as the synchronization pulse initiated by the master (see System Synchronization). So if it is not turned off during changes to the synchronization parameters, it can cause a false In Sync status.
Basic Digital Operation (Option 653/655/656/657) Multiple Baseband Generator Synchronization 4. Except for triggering, set the desired waveform parameters such as markers and sample clock. The baseband synchronization feature limits the trigger selections for both the master and slaves. If the current trigger settings include unsupported BBG synchronization parameters, the Agilent MXG/EXG generates a settings conflict error and changes the trigger settings.
Basic Digital Operation (Option 653/655/656/657) Multiple Baseband Generator Synchronization 1. On the master, press the Sync Slaves softkey. NOTE All of the signal generators in the master/slave system must be resynchronized when any changes are made to the master/slave settings or with the addition of a slave instrument, even if In Sync appears after pressing the Listen for Sync softkey on the slave instruments. 2.
Basic Digital Operation (Option 653/655/656/657) Understanding Option 012 (LO In/Out for Phase Coherency) with Multiple Baseband Generator Synchronization Understanding Option 012 (LO In/Out for Phase Coherency) with Multiple Baseband Generator Synchronization NOTE This section assumes that the previous section on Multiple Baseband Generator Synchronization has been read and understood. If not, refer to “Multiple Baseband Generator Synchronization” on page 225 before continuing.
Basic Digital Operation (Option 653/655/656/657) Understanding Option 012 (LO In/Out for Phase Coherency) with Multiple Baseband Generator Synchronization Table 8-5 Option 012 (LO In/Out for Phase Coherency) Equipment MIMO Configuration Parta Cable Length Notes 2x2 n/a As required SMA flexible cables are connected from the power splitter outputs to the LO inputs on the rear panel of both the master and the slave MXG/EXGs. Refer to Figure 8- 30 on page 234. 11636A n/a Power Divider, DC to 18 GHz.
Basic Digital Operation (Option 653/655/656/657) Understanding Option 012 (LO In/Out for Phase Coherency) with Multiple Baseband Generator Synchronization 2x2 MIMO (LO In/Out for Phase Coherency) Configuration For the 2x2 MIMO (LO In/Out for phase coherency) setup, the LO from the master MXG/EXG can be run through a power splitter and used as the LO input to both the master and the slave signal generators. No external source is required.
Basic Digital Operation (Option 653/655/656/657) Understanding Option 012 (LO In/Out for Phase Coherency) with Multiple Baseband Generator Synchronization Figure 8-31 3x3 and 4x4 MIMO (LO In/Out for Phase Coherency) Equipment Setup Note: A SMA flexible cable is recommended for the input to the 4–way splitter connections to the LO IN and LO OUT of the instruments with Option 012 (see page 232).
Basic Digital Operation (Option 653/655/656/657) Real-Time Applications Real-Time Applications The Agilent X- Series signal generators provide access to several real- time applications for signal creation. Figure 8-32 Real-Time Applications Softkeys page 146 page 316 page 316 page 251 page 369 page 310 page 178 Licensed Signal Studio applications are displayed here. Refer to www.agilent.com/find/signalstudio. For details on each key, use key help as described on page 44.
Basic Digital Operation (Option 653/655/656/657) Waveform Licensing Waveform Licensing Waveform licensing enables you to license waveforms that you generate and download from any Signal Studio application for unlimited playback in a signal generator. Each licensing option (221- 229) allows you to permanently license up to five waveforms or (250- 259) allows you to permanently license up to 50 waveforms of your choice (i.e. Waveform Option 22x or Option 25x are perpetual fixed waveform licenses).
Basic Digital Operation (Option 653/655/656/657) Waveform Licensing Waveform Licensing Softkeys Overview Figure 8-33 Waveform Licensing Softkeys Mode > Dual ARB > More Note: Waveforms licensed with Option 2xx cannot be exchanged for other waveforms. Once a waveform is locked into a license slot, that license is permanent and cannot be revoked or replaced. This softkey is only available if there is an Option 2xx license installed on the instrument.
Basic Digital Operation (Option 653/655/656/657) Waveform Licensing Figure 8-34 Waveform Licensing Softkeys Mode > Dual ARB > More > Waveform Licensing > Add Waveform to First Available Slot or Mode > Dual ARB > More > Waveform Licensing > Replace Waveform in Slot Note: Waveforms licensed with Option 2xx cannot be “exchanged”. Once a slot is locked, that license for the waveform in the locked slot is permanent and cannot be revoked or replaced.
Basic Digital Operation (Option 653/655/656/657) Waveform Licensing Figure 8-35 Waveform Licensing Softkeys Mode > Dual ARB > More > Waveform Licensing > Lock Waveform in Slot Press this softkey to confirm that you want to lock the waveform into the slot for permanent licensing. If the waveform has not been saved to internal storage, a warning message appears. Refer to Step 4 on page 243. This softkey is displayed if the waveform is not found in the internal storage memory of the signal generator.
Basic Digital Operation (Option 653/655/656/657) Waveform Licensing Table 8-6 Waveform Licensing Slot Status Messages Status Column Meaning Notes Available The slot has never had a waveform added to it. 50 slots are initially available for each Option 25x. 5 slots are initially available for each Option 22x. Locked MM/DD/YY The slot is locked and can no longer be modified. The waveform in this slot is licensed to this signal generator for unlimited playback.
Basic Digital Operation (Option 653/655/656/657) Waveform Licensing Example: Licensing a Signal Studio Waveform The following steps add a waveform file to a license slot and lock the slot for permanent playback. 1. Press Mode > Dual ARB > More > Waveform Utilities > Waveform Licensing The signal generator displays a catalog of files labeled: Catalog of BBG Segment Files in BBG Memory. 2. Use the arrow keys to highlight and select the file to be licensed. 3.
Basic Digital Operation (Option 653/655/656/657) Waveform Licensing 4. License the waveform: a. Press Lock Waveform in Slot. A warning is displayed: *** Waveform Lock Warning!!! ***. If necessary, verify you have selected the correct waveform you want for licensing by pressing Return. Figure 8-37 Waveform Lock Warning b. Press Confirm Locking Waveform. The licensing status of the slot will be changed to Locked MM/DD/YY. c.
Basic Digital Operation (Option 653/655/656/657) Waveform Licensing Waveform Licensing Warning Messages Figure 8-39 This standard warning is displayed every time a waveform is selected to be locked. This notification indicates that one of the available “license slots” is about to be used from Option 2xx. ALWAYS make backup copies of waveforms in a separate non–volatile memory in case a file is deleted or lost from the instrument’s internal storage.
9 Adding Real–Time Noise to a Signal (Option 403) Before using this information, you should be familiar with the basic operation of the signal generator. If you are not comfortable with functions such as setting the power level and frequency, refer to Chapter 3, “Basic Operation,” on page 43 and familiarize yourself with the information in that chapter. This feature is available only in Agilent X- Series vector signal generators with Option 431.
Adding Real–Time Noise to a Signal (Option 403) Adding Real–Time Noise to a Dual ARB Waveform Figure 9-1 Real Time I/Q Baseband AWGN Softkeys For details on each key, use key help as described on page 44. This is the stand–alone Real–Time AWGN and the 2nd page of the Modulation Mode menu (see page 251). The state of the noise (on or off) is shown on the display. Figure 9-6 on page 250 provides additional details on these settings.
Adding Real–Time Noise to a Signal (Option 403) Adding Real–Time Noise to a Dual ARB Waveform Figure 9-2 Real Time I/Q Baseband AWGN - Power Control Mode Softkeys Mode > Dual ARB > Arb Setup > Real-Time AWGN Setup For details on each key, use key help as described on page 44. Figure 9-6 on page 250 provides additional details on these settings.
Adding Real–Time Noise to a Signal (Option 403) Adding Real–Time Noise to a Dual ARB Waveform Figure 9-3 Real Time I/Q Baseband AWGN - Noise Mux Menu Softkeys Mode > Dual ARB > Arb Setup > Real-Time AWGN Setup > More Figure 9-6 on page 250 provides additional details on these settings. Enables diagnostic control of additive noise, so that only the noise, only the carrier, or the sum of both the noise and the carrier are output from the internal baseband generator.
Adding Real–Time Noise to a Signal (Option 403) Adding Real–Time Noise to a Dual ARB Waveform Figure 9-5 Real Time I/Q Baseband AWGN - Eb/N0 Adjustment Softkeys Mode > Dual ARB > Arb Setup > Real-Time AWGN Setup Figure 9-6 on page 250 provides additional details on these settings. Selects either the Carrier to Noise Ratio (C/N) or energy per bit over noise power density at the receiver (Eb/No) as the variable controlling the ratio of the carrier power to noise power in the carrier bandwidth.
Adding Real–Time Noise to a Signal (Option 403) Adding Real–Time Noise to a Dual ARB Waveform Figure 9-6 Carrier to Noise Ratio Components Carrier Bandwidth (CBW) is typically the occupied bandwidth of the carrier and the Noise Bandwidth is the flat noise bandwidth (NBW). Noise BW (NBW) = flat noise bandwidth Carrier BW (CBW) RMS (total carrier power) Carrier The carrier now appears larger because of the added noise power.
Adding Real–Time Noise to a Signal (Option 403) Using Real Time I/Q Baseband AWGN Using Real Time I/Q Baseband AWGN Figure 9-7 Real Time I/Q Baseband AWGN Softkeys For details on each key, use key help as described on page 44. Use the following steps to apply 10 MHz bandwidth noise to a 500 MHz, –10 dBm carrier. 1. Configure the noise: a. Preset the signal generator. b. Press Mode > More > Real-Time AWGN c. Press Bandwidth > 10 > MHz. 2.
Adding Real–Time Noise to a Signal (Option 403) Using Real Time I/Q Baseband AWGN 252 Agilent X-Series Signal Generators User’s Guide
10 Digital Signal Interface Module (Option 003/004) This chapter provides information on the N5102A Baseband Studio Digital Signal Interface Module. These features are available only in N5172B/82B Vector Signal Generators with Options 003/004 and 653/655/656/657.
Digital Signal Interface Module (Option 003/004) Clock Timing Figure 10-1 Data Setup Menu for a Parallel Port Configuration Most significant bit Least significant bit Clock and sample rates The N5102A module clock rate is set using the Clock Rate softkey and has a range of 1 kHz to 400 MHz. The sample rate is automatically calculated and has a range of 1 kHz to 200 MHz. These ranges can be smaller depending on logic type, data parameters, and clock configuration.
Digital Signal Interface Module (Option 003/004) Clock Timing The levels will degrade above the warranted level clock rates, but they may still be usable. Serial Port Configuration Clock Rates For a serial port configuration, the lower clock rate limit is determined by the word size (word size and sample size are synonymous), while the maximum clock rate limit remains constant at 150 MHz for LVTTL and CMOS logic types, and 400 MHz for an LVDS logic type. The reverse is true for the sample rate.
Digital Signal Interface Module (Option 003/004) Clock Timing sample rate is reduced by the clocks per sample value when the value is greater than one. For an IF signal or an input signal, clocks per sample is always set to one. Refer to Table 10- 5 for the Output mode parallel and parallel interleaved port configuration clock rates.
Digital Signal Interface Module (Option 003/004) Clock Timing Figure 10-2 Clock Source Selection External and Device selection: Set to match the clock rate of the applied clock signal internal selection: Set the internal clock rate. Internal clock source selection: Set the frequency of the applied reference signal. When you select a clock source, you must let the N5102A module know the frequency of the clock signal using the Clock Rate softkey.
Digital Signal Interface Module (Option 003/004) Clock Timing Signal Generator Frequency Reference Connections When a frequency reference is connected to the signal generator, it is applied the REF In rear panel connector. Figure 10-3 Frequency Reference Setup Diagrams for the N5102A Module Clock Signal Internally Generated Clock Device (DUT) Supplied Clock NOTE: Use only one of the two signal generator frequency reference inputs.
Digital Signal Interface Module (Option 003/004) Clock Timing Externally Supplied Clock NOTE: Use only one of the two signal generator frequency reference inputs. Clock Timing for Parallel Data Some components require multiple clocks during a single sample period. (A sample period consists of an I and Q sample). For parallel data transmissions, you can select one, two, or four clocks per sample.
Digital Signal Interface Module (Option 003/004) Clock Timing Figure 10-4 Clock Sample Timing for Parallel Port Configuration 1 Clock Per Sample 1 Sample Period 1 Clock Clock and sample rates are the same Clock I sample 4 bits per word Q sample 4 bits per word 260 Agilent X-Series Signal Generators User’s Guide
Digital Signal Interface Module (Option 003/004) Clock Timing 2 Clocks Per Sample Sample rate decreases by a factor of two 1 Sample Period 2 Clocks Clock I sample 4 bits per word Q sample 4 bits per word 4 Clocks Per Sample Sample rate decreases by a factor of four 1 Sample Period 4 Clocks Clock I sample 4 bits per word Q sample 4 bits per word Agilent X-Series Signal Generators User’s Guide 261
Digital Signal Interface Module (Option 003/004) Clock Timing Clock Timing for Parallel Interleaved Data The N5102A module provides the capability to interleave the digital I and Q samples. There are two choices for interleaving: • IQ, where the I sample is transmitted first • QI, where the Q sample is transmitted first When parallel interleaved is selected, all samples are transmitted on the I data lines.
Digital Signal Interface Module (Option 003/004) Clock Timing 2 Clocks Per Sample The I sample is transmitted for one clock period and the Q sample is transmitted during the second clock period; the sample rate decreases by a factor of two.
Digital Signal Interface Module (Option 003/004) Clock Timing Clock Timing for Serial Data Figure 10- 6 shows the clock timing for a serial port configuration. Notice that the serial transmission includes frame pulses that mark the beginning of each sample where the clock delineates the beginning of each bit. For serial transmission, the clock and the bit rates are the same, but the sample rate varies depending on the number of bits per word that are entered using the Word Size softkey.
Digital Signal Interface Module (Option 003/004) Connecting the Clock Source and the Device Under Test Figure 10-7 Clock Phase and Skew Adjustments 90 degree phase adjustment Clock skew adjustment Phase and skew adjusted clock Phase adjusted clock Clock Data Connecting the Clock Source and the Device Under Test As shown in Figure 10- 3 on page 258, there are numerous ways to provide a common frequency reference to the system components (signal generator, N5102A module, and the device under test).
Digital Signal Interface Module (Option 003/004) Connecting the Clock Source and the Device Under Test Figure 10-8 Example Setup using the Signal Generator 10 MHz Frequency Reference Signal generator 10 MHz Out Common Freq Ref cable Freq Ref connector Device under test Break-out board Device interface connection NOTE User furnished ribbon cable(s) connect between the device and break-out board. The clock to the device is in the ribbon cable.
Digital Signal Interface Module (Option 003/004) Connecting the Clock Source and the Device Under Test 4. Refer to Figure 10- 8. Connect the break- out board to the Device Interface connector on the N5102A module. 5. Connect the device to the break- out board.
Digital Signal Interface Module (Option 003/004) Data Types Data Types The following block diagram indicates where in the signal generation process the data is injected for input mode or tapped for output mode.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Output Mode Operating the N5102A Module in Output Mode This section shows how to set the parameters for the N5102A module using the signal generator UI in the output direction. Each procedure contains a figure that shows the softkey menu structure for the interface module function being performed.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Output Mode Press N5102A Interface to access the UI (first- level softkey menu shown in Figure 10- 10) that is used to configure the digital signal interface module. Notice the graphic in the signal generator display, showing a setup where the N5102A module is generating its own internal clock signal. This graphic changes to reflect the current clock source selection.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Output Mode Choosing the Logic Type and Port Configuration Figure 10-11Logic and Port Configuration Softkey Menus 1. Refer to Figure 10- 11. Press the Logic Type softkey. From this menu, choose a logic type. CAUTION Changing the logic type can increase or decrease the signal voltage level going to the device under test.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Output Mode setup. 4. Select the port configuration for the device. Selecting the Output Direction Press Data Setup > Direction Input Output to Output and press Return. NOTE If Option 003 is the only option installed, the direction softkey will be unavailable and the mode will always be output. With both Option 003 (output mode) and Option 004 (input mode) installed, the default direction is output.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Output Mode Figure 10-13 Data Setup Softkey Menu with Parallel Port Configuration Inactive for ARB formats Inactive for word size = 16 bits Inactive for a serial port configuration Available only while in output mode Frame polarity is active for a serial port configuration 2. If a real- time modulation format or the real- time modulation filter feature in Dual ARB is being used, press the Data Type softkey.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Output Mode selection should be used to avoid double filtering. 3. Select the data type that is appropriate for the test. 4. Press the Numeric Format softkey. From this menu, select how the binary values are represented. Selecting 2’s complement allows both positive and negative data values. Use the Offset Binary selection when components cannot process negative values. 5. Select the numeric format required for the test. 6.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Output Mode Figure 10-14 Clock Setup Menu Location Accesses the Clock Setup Menu From this softkey menu, set all of the clock parameters that synchronize the clocks between the N5102A module and the signal generator. You can also change the clock signal phase so the clock occurs during the valid portion of the data. Figure 10- 15 shows the clock setup menu.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Output Mode source selection discussed later in this procedure. The bottom graphic shows the clock position relative to the data.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Output Mode This error is reported when the output FIFO is overflowing in 806 the digital module. This error can be generated if an external clock or its reference is not set up properly, or if the internal VCO is unlocked. Digital module output FIFO underflow error; There are not enough samples being produced for the current clock rate. Verify that the digital module clock is set up properly.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Output Mode b. Press the Clock Rate softkey and enter the appropriate clock rate. Table 10- 7 provides a quick view of the settings and connections associated with each clock source selection.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Output Mode Timing for Phase and Skew Adjustments” on page 264 for more information on skew settings. 10. Enter the skew adjustment that best positions the clock with the valid portion of the data. 11. Press the Clock Polarity Neg Pos softkey to Neg. This shifts the clock signal 180 degrees, so that the data starts during the negative clock transition. This has the same affect as selecting the 180 degree phase adjustment. 12.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Input Mode Operating the N5102A Module in Input Mode This section shows how to set the parameters for the N5102A module using the signal generator UI in the input direction. Each procedure contains a figure that shows the softkey menu structure for the interface module function being performed. Refer to “Connecting the Clock Source and the Device Under Test” on page 265 and configure the test setup.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Input Mode Figure 10-17 N5102A Interface Menu Internal clock going to the DUT Line is grayed out until the N5102A module interface is turned on Agilent X-Series Signal Generators User’s Guide 281
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Input Mode Selecting the Input Direction If both Option 003 (output mode) and Option 004 (input mode) are installed, you must select the input direction. Press Data Setup > Direction Input Output to Input and press Return. NOTE If only Option 004 is installed, the direction softkey will be unavailable and the mode will always be input.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Input Mode 2. Select the logic type required for the device being tested. A caution message is displayed whenever a change is made to the logic types, and a softkey selection appears asking for confirmation. 3. Refer to Figure 10- 18. Press the Port Config softkey. In this menu, select either a serial, parallel, or parallel interleaved data transmission.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Input Mode 804 module. Verify that the input clock rate matches the specified clock rate under the clock setup menu. Digital module input FIFO underflow error; There are not enough samples being produced for the current clock rate. Verify that the digital module clock is set up properly. This error is reported when the digital module clock setup is not synchronized with the rate the samples are entering the digital module.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Input Mode • clock polarity selection 2. Press the Clock Source softkey. From this menu, select the clock signal source. With each selection, the clock routing display in the signal generator clock setup menu will change to reflect the current clock source. This will be indicated by a change in the graphic. 3. Select the clock source.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Input Mode Table 10-8 Clock Source Settings and Connectors Clock Source Softkeys Reference Frequency N5102A Module Connection Clock Rate1 External • Device • Internal2 • • Freq Ref Ext Clock In Device Interface • • • 1For the Internal selection, this sets the internal clock rate. For the External and Device selections, this tells the interface module the rate of the applied clock signal.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Input Mode 9. Press the Clock Polarity Neg Pos softkey to Neg. This shifts the clock signal 180 degrees, so that the data starts during the negative clock transition. This has the same affect as selecting the 180 degree phase adjustment. 10. Make the clock polarity selection that is required for the device being tested. 11. Press the Return hardkey to return to the first- level softkey menu.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Input Mode Figure 10-22 Data Setup Softkey Menu with Parallel Port Configuration Inactive for a serial port configuration Only available when Data Type is Pre-FIR Samples Only available when the N5102A digital module is turned on and using input mode Frame polarity is active for a serial port configuration 288 Agilent X-Series Signal Generators User’s Guide
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Input Mode 2. Press the Data Type softkey. In this menu, select the data type to be either filtered (Samples) or unfiltered (Pre-FIR Samples). The selection is dependent on the test needs and the device under test. However if the device being tested already incorporates FIR filters, the Pre-FIR Samples selection should be used to avoid double filtering. Refer to “Data Types” on page 268, for more information. 3.
Digital Signal Interface Module (Option 003/004) Operating the N5102A Module in Input Mode 6. Press the More (1 of 2) softkey. From this softkey menu, select the bit order, swap I and Q, the polarity of the data, and access menus that provides data negation, scaling, and filtering parameters. 7. Press the Data Negation softkey. Negation differs from changing the I and Q polarity.
11 BERT (Option UN7) The bit error rate test (BERT) capability allows you to perform bit error rate (BER) analysis on digital communications equipment. This enables functional and parametric testing of receivers and components including sensitivity and selectivity. This feature is available in X- Series vector signal generators (N5172B and N5182B).
BERT (Option UN7) Bit Error Rate Tester–Option UN7 Bit Error Rate Tester–Option UN7 The bit error rate test (BERT) capability allows you to perform bit error rate (BER) analysis on digital communications equipment. This enables functional and parametric testing of receivers and components including sensitivity and selectivity. Block Diagram When measuring BER, a clock signal that corresponds to the unit under test (UUT) output data must be input to the BER CLK IN connector.
BERT (Option UN7) Bit Error Rate Tester–Option UN7 Figure 11-2 • When the Clock Gate Off On softkey is set to Off: The clock signal in both “A” and “B” parts is effective and no gate function is required. Therefore, the bit error rate is measured using the clock and data signal in both “A” and “B” parts. • When the Clock Gate Off On softkey is set to On, and the Clock Gate Polarity Neg Pos softkey is set to Pos: The clock signal in “A” part is effective.
BERT (Option UN7) Bit Error Rate Tester–Option UN7 Figure 11-3 294 Agilent X-Series Signal Generators User’s Guide
BERT (Option UN7) Bit Error Rate Tester–Option UN7 Clock Delay Function In this example, the clock delay function is off. Figure 11- 4 shows the input of the internal error detector of UN7 through AUX I/O and indicates that the data is delayed from the clock. Figure 11-4 CH1 CH2 CH1: BER TEST OUT (pin 17 of AUX I/O connector) CH2: BER MEAS END (pin 15 of AUX I/O connector) In this example, the clock delay function is on.
BERT (Option UN7) Bit Error Rate Tester–Option UN7 Gate Delay Function in the Clock Mode To use this function, the clock must be set to continuous mode. In this example, the clock is used to delay the gate function. The clock of the internal error detector was gated by the gate signal which is delayed by two clocks. Figure 11- 6 shows that CH0 and CH1 are the input of the clock and data from the rear panel input connectors of UN7. CH2 is the gated clock through the AUX I/O connector.
BERT (Option UN7) Bit Error Rate Tester–Option UN7 Triggering This section describes the operating principles of the triggering function for Option UN7. To see the signal flow of the triggering function refer to Figure 11- 7.
BERT (Option UN7) Bit Error Rate Tester–Option UN7 In this example, the triggering sequence is where you have an incoming data clock and data bit sequences, the trigger is active, and the BERT measurement begins. Refer to Figure 11- 8.
BERT (Option UN7) Bit Error Rate Tester–Option UN7 In this example, synchronization occurs after receiving a trigger. The reference data is generated by stored data bits. If the BERT measurement accepts data bits immediately after receiving a trigger, set the trigger delay to On and the trigger delay count to a value corresponding to the data format. For PN9 set the delay to 9. Refer to Figure 11- 9.
BERT (Option UN7) Bit Error Rate Tester–Option UN7 In this example, the triggering sequence is where the trigger delay is active with a cycle count. The reference data is generated by stored data bits. If the BERT measurement accepts data bits immediately after receiving a trigger, set the trigger delay to On and the trigger delay count to a value corresponding to the data format. For PN9 set the delay to 9.
BERT (Option UN7) Bit Error Rate Tester–Option UN7 Special Pattern Ignore Function The special pattern ignore function is especially useful when performing BERT analysis on radios that generate consecutive 0’s or 1’s data for traffic channels when they fail to detect the Unique Word or lose synchronization. If 160 or more consecutive incoming data bits are either 1’s or 0’s, and the Spcl Pattern Ignore Off On softkey is set to On, then all of the consecutive 0’s or 1’s are ignored.
BERT (Option UN7) Bit Error Rate Tester–Option UN7 Figure 11-12 Repeat Measurements Example Testing Signal Definitions The timing diagram Figure 11- 13, “Testing Signal Definitions,” shows the relationships between a trigger event and the output signals at the BER MEAS END and BER TEST OUT connectors. If a BER MEAS END signal stays high following a trigger event, the BERT measurement is in progress and other trigger events are ignored. This state is stored in the status register and can be queried.
BERT (Option UN7) Bit Error Rate Tester–Option UN7 • T2 is a firmware handling time measured from the falling edge of a BER TEST OUT signal to the falling edge of the BER MEAS END signal. • T3 is a minimum requirement time measured from the falling edge of the BER MEAS END signal to the next trigger event. T3 should be greater than 0 second.
BERT (Option UN7) Verifying BERT Operation Verifying BERT Operation The following procedures verify the operation of the signal generator’s bit error rate test (BERT) function. The tests can be performed as part of a daily validation routine or can be used whenever you want to check the validity of your BERT measurements. The procedures check the signal generator’s BERT operation and do not ensure system performance to specifications.
BERT (Option UN7) Verifying BERT Operation Rear Panel Connectors for BERT Configuration BER Gate In BER Clock In AUX I/O BER Meas End BER Sync Loss BER Gate Out BER Data In BER Test Out Figure 11-14 BER No Data GND 2. Press the Preset hardkey. This configures the signal generator to a pre- defined state. 3. Press the Aux Fctn hardkey. 4.
BERT (Option UN7) Verifying BERT Operation Figure 11-15 306 Self-Test Mode Results Agilent X-Series Signal Generators User’s Guide
BERT (Option UN7) Verifying BERT Operation Measurement Example Using Custom Digital Modulation (Requires Option 431) The following steps set up the signal generator for a BERT measurement using Custom Digital Modulation. 1. Refer to Figure 11- 14 and make the following connections on the signal generator’s rear panel. • DATA OUT (Aux I/O connector pin 33) to BER DATA IN (BNC connector labeled EVENT 1). • DATA CLK OUT (Aux I/O connector pin 7) to BER CLK IN (BNC connector labeled BB TRIG1). 2.
BERT (Option UN7) Verifying BERT Operation Figure 11-16 Configuration Using Custom Digital Modulation BERT Verification 1. Press BERT Trigger to Immediate. Notice the cycle counter updating in the lower left- hand corner of the signal generator display. 2. Disconnect the cable connecting the DATA OUT to BER DATA IN connectors. Notice the No Data annunciator in the lower left corner of the display and the BER result is approximately 50%. The Error Bits counter updates the error bit count.
12 Real–Time Phase Noise Impairments (Option 432) Before using this information, you should be familiar with the basic operation of the signal generator. If you are not comfortable with functions such as setting the power level and frequency, refer to Chapter 3, “Basic Operation,” on page 43 and familiarize yourself with the information in that chapter. This feature is available only in Agilent X- Series vector signal generators with Option 431.
Real–Time Phase Noise Impairments (Option 432) Real–Time Phase Noise Impairment Real–Time Phase Noise Impairment This feature lets you degrade the phase noise performance of the signal generator by controlling two frequency points and an amplitude value. The signal generator adds this phase noise to the phase noise normally produced by the signal generator. This feature appears in each of the arb formats and as a stand–alone menu.
Real–Time Phase Noise Impairments (Option 432) The Agilent X-Series Phase Noise Shape and Additive Phase Noise Impairments The Agilent X-Series Phase Noise Shape and Additive Phase Noise Impairments Phase Noise Plots Without Phase Noise Impairment −50 dBc/Hz −50 dBc/Hz Flat mid–frequency offset The Agilent X-Series vector signal generator demonstrates a definitive shape to its phase noise plot.
Real–Time Phase Noise Impairments (Option 432) The Agilent X-Series Phase Noise Shape and Additive Phase Noise Impairments Phase Noise Plots With Phase Noise Impairments −50 dBc/Hz Flat mid–frequency offset characteristics (Lmid) −50 dBc/Hz Resultant phase noise plot f1 f2 No additive phase noise −50 dBc/Hz 100 Hz Flat mid–frequency offset characteristics (Lmid) When turned on, this phase noise is added to the base phase noise of the signal generator.
Real–Time Phase Noise Impairments (Option 432) Understanding the Phase Noise Adjustments Understanding the Phase Noise Adjustments The signal generator bases the resultant phase noise shape on three settings, Lmid (amplitude), f1 (start frequency), and f2 (stop frequency). The range for Lmid is coupled to f2, so as f2 increases in value, Lmid’s upper boundary decreases.
Real–Time Phase Noise Impairments (Option 432) DAC Over–Range Conditions and Scaling DAC Over–Range Conditions and Scaling When using phase noise impairment, it is possible to create a DAC over–range condition, which causes the signal generator to generate an error. To minimize this condition with the phase noise impairment feature, the Agilent X- Series signal generator incorporates an automatic DAC over–range protection feature that scales down the I/Q data.
13 Custom Digital Modulation (Option 431) Before using this information, you should be familiar with the basic operation of the signal generator. If you are not comfortable with functions such as setting the power level and frequency, refer to Chapter 3, “Basic Operation,” on page 43 and familiarize yourself with the information in that chapter. This feature is available only in Agilent X- Series vector signal generators with Option 431.
Custom Digital Modulation (Option 431) Custom Modulation Custom Modulation For creating custom modulation, the signal generator offers two modes of operation: the ARB custom modulation mode and the real- time custom modulation mode. The ARB custom modulation mode has built- in modulation formats such as NADC or GSM and pre- defined modulation types such as BPSK and 16QAM that can be used to create a signal. It also provides the flexibility to modify the digital format’s attributes.
Custom Digital Modulation (Option 431) Custom Modulation Figure 13-1 ARB Custom Modulation Softkeys page 146 Enables the current ARB custom modulation settings. page 350 page 321 This softkey changes, depending on the selected mode of modulation. Available only when Multicarrier is Off. page 200 page 236 page 318 page 369 page 350 page 178 Available only when Multicarrier is On. page 147 For details on each key, use key help as described on page 44.
Custom Digital Modulation (Option 431) Custom Modulation Figure 13-2 Quick Setup Softkeys Mode > ARB Custom Modulation > Single Carrier Setup This softkey label shows the currently selected modulation standard. page 319 page 343 page 353 page 320 Press Symbol Rate softkey and use numeric keypad to change value as required. The default (initial) Symbol Rate maximum range value is dependent upon the modulation standard selected with the Quick Setup softkey.
Custom Digital Modulation (Option 431) Custom Modulation Figure 13-3 Mod Type Softkeys Mode > ARB Custom Modulation > Single Carrier Setup page 318 page 353 page 339 page 320 These symbol maps utilize Gray coded bit mapping. Sets the modulation depth for the Amplitude Shift Keying (ASK). These symbol maps are consistent with the symbol maps in the VSA software. For details on each key, use key help as described on page 44.
Custom Digital Modulation (Option 431) Custom Modulation Figure 13-4 Custom Modulation Formats and Applications Figure 13-5 Store Custom Dig Mod State Softkeys Mode > ARB Custom Modulation > Single Carrier Setup > Store Custom Dig Mod State page 342 Catalog displays digital modulation (DMOD) files that have been previously saved. For details on each key, use key help as described on page 44.
Custom Digital Modulation (Option 431) Custom Modulation Figure 13-6 Real-Time Custom Modulation Softkeys page 146 page 316 page 236 Enables the current custom real-time modulation settings. page 322 page 369 Opens a menu from which you can set burst shape parameters. page 362 page 245 page 310 page 200 page 178 For details on each key, use key help as described on page 44.
Custom Digital Modulation (Option 431) Custom Modulation Figure 13-7 Modulation Setup Softkeys Mode > Real-Time Custom Modulation > Modulation Setup This softkey label shows the currently selected modulation page 323 page 353 page 325 Press Symbol Rate softkey and use numeric keypad to change value as required. The default (initial) Symbol Rate maximum range value is dependent upon the modulation standard selected with the Quick Setup softkey.
Custom Digital Modulation (Option 431) Custom Modulation Figure 13-8 Modulation Type Softkeys Mode > Real-Time Custom Modulation > Modulation Setup page 322 page 344 page 353 page 345 page 324 These symbol maps utilize Gray coded bit mapping. These symbol maps are consistent with the symbol maps in the VSA software. For details on each key, use key help as described on page 44.
Custom Digital Modulation (Option 431) Creating and Using Bit Files Creating and Using Bit Files This procedure teaches you how to use the Bit File Editor to create, edit, and store user- defined files for data transmission within real time I/Q baseband generated modulation. For this example, a user file is defined within a custom digital communications format.
Custom Digital Modulation (Option 431) Creating and Using Bit Files Figure 13-9 Data Selection Softkeys Mode > Real-Time Custom Modulation > Modulation Setup Press this key to select from a number of P sequences and whether to invert them. Press this key to select data patterns of 1s and 0s. Press this key to create, select, and edit files to use as the bit pattern. For details on each key, use key help as described on page 44. Press this key to select a Pattern RAM (PRAM) file.
Custom Digital Modulation (Option 431) Creating and Using Bit Files Figure 13-10 Bit File Display Offset (in Hex) NOTE Bit Data Cursor Position Indicator (in Hex) Hexadecimal Data File Name Indicator When you create new file, the default name appears as UNTITLED, or UNTITLED1, and so forth. This prevents overwriting previous files. Entering Bit Values Bit data is entered into the table editor in 1- bit format.
Custom Digital Modulation (Option 431) Creating and Using Bit Files Figure 13-11 Entering Bit Values Enter these bit values Cursor Position Indicator Hexadecimal Data Renaming and Saving a User File In this example, you learn how to store a user file. If you have not created a user file, complete the steps in the previous section, “Creating a User File” on page 325. 1. Press More (1 of 2) > Rename > Editing Keys > Clear Text. 2.
Custom Digital Modulation (Option 431) Creating and Using Bit Files Recalling a User File In this example, you learn how to recall a user- defined data file from the memory catalog. If you have not created and stored a user- defined data file, complete the steps in the previous sections, “Creating a User File” on page 325 and “Renaming and Saving a User File” on page 327. 1. Press Preset. 2. Press Mode > Real-Time Custom Modulation > Modulation Setup > Data > User File. 3. Highlight the file USER1. 4.
Custom Digital Modulation (Option 431) Creating and Using Bit Files Inverting Bit Values 1. Press 1011. This inverts the bit values that are positioned 4C through 4F. Notice that hex data in this row has now changed to 76DB6DB6, as shown in the following figure. Figure 13-13 Inverting Bit Values Bits 4C through 4F are inverted Hex Data changed Applying Bit Errors to a User File In this example, you learn how to apply bit errors to a user- defined data file.
Custom Digital Modulation (Option 431) Using Customized Burst Shape Curves Using Customized Burst Shape Curves You can adjust the shape of the rise time curve and the fall time curve using the Rise Shape and Fall Shape editors. Each editor allows you to enter up to 256 values, equidistant in time, to define the shape of the curve. The values are then resampled to create the cubic spline that passes through all of the sample points.
Custom Digital Modulation (Option 431) Using Customized Burst Shape Curves User-Defined Values User-Defined Values Power 1 0 Rise Delay Rise Time Fall Delay Fall Time Time Burst shape maximum rise and fall time values are affected by the following factors: • the symbol rate • the modulation type When the rise and fall delays equal 0, the burst shape is attempting to synchronize the maximum burst shape power to the beginning of the first valid symbol and the ending of the last valid symbol of the
Custom Digital Modulation (Option 431) Using Customized Burst Shape Curves The signal generator firmware computes optimum burst shape based on the settings you’ve chosen for modulation. You can further optimize burst shape by lining up the data portion with the modulation. For example, if you’re designing a new modulation scheme, do the following: • Adjust the modulation and filtering to set the spectrum you want. • Adjust the burst rise and fall delay and rise and fall time for the timeslots.
Custom Digital Modulation (Option 431) Using Customized Burst Shape Curves Figure 13-14 Burst Shape Softkeys Mode > Real-Time Custom Modulation For details on each key, use key help as described on page 44. Creating a User-Defined Burst Shape Curve Using this procedure, you learn how to enter rise shape sample values and mirror them as fall shape values to create a symmetrical burst curve.
Custom Digital Modulation (Option 431) Using Customized Burst Shape Curves Entering Sample Values Use the sample values in the following table. Rise Shape Editor Sample Value Sample Value 0 0.000000 4 0.830000 1 0.400000 5 0.900000 2 0.600000 6 1.000000 3 0.750000 1. Highlight the value (1.000000) for sample 1. 2. Press .4 > Enter. 3. Press .6 > Enter. 4. Enter the remaining values for samples 3 through 6 from the table above. 5.
Custom Digital Modulation (Option 431) Using Customized Burst Shape Curves Display the Burst Shape Press Display Burst Shape. This displays a graphical representation of the waveform’s rise and fall characteristics, as shown in Figure 13- 16. Figure 13-16 Burst Shape To return the burst to the default conditions, press the following keys: Return > Return > Return > Confirm Exit From Table Without Saving > Restore Default Burst Shape. Storing a User-Defined Burst Shape Curve 1.
Custom Digital Modulation (Option 431) Using Customized Burst Shape Curves 2. Press Mode > Real-Time Custom Modulation > Burst Shape > Burst Shape Type > User File. 3. Highlight the desired burst shape file (for example, NEWBURST). 4. Press Select File. The selected burst shape file is now applied to the current real time I/Q baseband digital modulation state.
Custom Digital Modulation (Option 431) Using the Arbitrary Waveform Generator Using the Arbitrary Waveform Generator This section teaches you how to build dual arbitrary (ARB) waveform files containing custom digital modulation for testing component designs. Figure 13-17 Adding Custom Modulation to a Waveform Mode > ARB Custom Modulation > Single Carrier Setup This softkey label updates to reflect the current modulation type.
Custom Digital Modulation (Option 431) Using the Arbitrary Waveform Generator Configuring the RF Output 1. Set the RF output frequency to 891 MHz. 2. Set the output amplitude to −5 dBm. 3. Press RF On/Off. The predefined EDGE signal is now available at the signal generator’s RF OUTPUT connector.
Custom Digital Modulation (Option 431) Using the Arbitrary Waveform Generator Creating a Custom Digital Modulation State In this procedure, you learn how to set up a single–carrier NADC digital modulation with customized modulation type, symbol rate, and filtering. Figure 13-18 Setting a Digital Modulation Filter Mode > ARB Custom Modulation > Single Carrier Setup This softkey label updates to reflect the current modulation standard. page 343 This softkey sets the filter shape.
Custom Digital Modulation (Option 431) Using the Arbitrary Waveform Generator Figure 13-19 Modifying a Digital Modulation Type Mode > ARB Custom Modulation > Single Carrier Setup > Modulation Type > Select These softkeys, open a menu to select an existing user I/Q or user FSK file that can be selected and applied to the current modulation type. For details on each key, use key help as described on page 44. Note: This is the 2nd page of the PSK menu. Note: This is the 2nd page of the QPSK menu.
Custom Digital Modulation (Option 431) Using the Arbitrary Waveform Generator Selecting the Filter 1. In the Setup Mod menu (page 339), press Filter > Select > Nyquist. 2. Press Return > Return. Generating the Waveform Press Digital Modulation Off On. This generates a waveform with the custom, single–carrier NADC, digital modulation state created in the previous sections. The display changes to Dig Mod Setup: NADC (Modified).
Custom Digital Modulation (Option 431) Using the Arbitrary Waveform Generator Figure 13-20 Storing a Custom Digital Modulation State Mode > ARB Custom Modulation > Single Carrier Setup page 45 These keys manage the table of DMOD files in internal storage. Catalog displays DMOD files that have been previously saved by the user. For details on each key, use key help as described on page 44. 1. Return to the top–level ARB Custom Modulation menu, where Digital Modulation Off On is the first softkey. 2.
Custom Digital Modulation (Option 431) Using the Arbitrary Waveform Generator Recalling a Custom Digital Modulation State Using this procedure, you will learn how to recall a custom digital modulation state from signal non–volatile memory.
Custom Digital Modulation (Option 431) Using the Arbitrary Waveform Generator Defining a Modulation You can build a unique modulation by utilizing two tools, the FSK table editor or the I/Q table editor. These tables map data onto specific absolute modulation states. To map transitions between states, a differential table editor is provided.
Custom Digital Modulation (Option 431) Using the Arbitrary Waveform Generator Figure 13-22 FSK Table Editor Mode > Real-Time Custom Modulation > Modulation Setup > Modulation Type > Define User FSK For details on each key, use key help as described on page 44. Mapping I/Q Values with the I/Q Table Editor In most digital radio systems, the frequency of the carrier is fixed so only phase and magnitude need to be considered.
Custom Digital Modulation (Option 431) Using the Arbitrary Waveform Generator Figure 13-23 I/Q Constellation Diagram By modulating the carrier to one of several predetermined positions in the I/Q plane, you can then transmit encoded information. Each position or state represents a certain bit pattern that can be decoded at the receiver. The mapping of the states at each symbol decision point on the I/Q plane is referred to as a constellation diagram.
Custom Digital Modulation (Option 431) Using the Arbitrary Waveform Generator Utilizing this I/Q mapping flexibility, you can create unique modulation schemes. For example, a circular constellation arrangement called a STAR QAM is easily implemented and saved for later recall with the real- time I/Q baseband generator. Figure 13- 25 shows that the STAR QAM has 16 states or symbols. Four data bits define each symbol. Thus, the diagram and the table are equivalents. Create a STAR QAM Modulation Scheme 1.
Custom Digital Modulation (Option 431) Using the Arbitrary Waveform Generator Figure 13- 26 shows the X- Series setup and the I/Q display. Figure 13-26 Custom Modulation and I/Q Display Hints for Constructing Modulations • The map is limited to 16 total signal levels for I and Q combined. The readout on the right- hand side of the table tracks the number of I and Q levels utilized. Levels are I or Q values. Figure 13- 27 shows an 8PSK signal built in two different ways.
Custom Digital Modulation (Option 431) Using the Arbitrary Waveform Generator Figure 13-27 8PSK Signal Built Two Ways Figure 13-28 16QAM I/Q Map with Even and Uneven Levels Agilent X-Series Signal Generators User’s Guide 349
Custom Digital Modulation (Option 431) Using the Arbitrary Waveform Generator Creating a Custom Multicarrier Digital Modulation State In this procedure, you learn how to customize a predefined, multicarrier, digital modulation setup by creating a custom, 3–carrier EDGE, digital modulation state.
Custom Digital Modulation (Option 431) Using the Arbitrary Waveform Generator Creating a Multicarrier Digital Modulation Setup 1. Press Preset. 2. Press Mode > ARB Custom Modulation > Multicarrier Off On to On. 3. Press Multicarrier Setup > Select Carrier and Initialize Table > Carrier Setup > EDGE > Done. Modifying Carrier Frequency Offset 1. Highlight the Freq Offset value (500.000 kHz) for the carrier in row 2. 2. Press –625 > kHz. Modifying Carrier Power 1. Highlight the Power value (0.
Custom Digital Modulation (Option 431) Using the Arbitrary Waveform Generator Storing a Custom Multicarrier Digital Modulation State Using this procedure, you learn how to store a custom, multicarrier, digital modulation state to non–volatile memory. If you have not created a custom, multicarrier, digital modulation state, complete the steps in the previous section, “Creating a Custom Multicarrier Digital Modulation State” on page 350.
Custom Digital Modulation (Option 431) Using Finite Impulse Response (FIR) Filters with Custom Modulation Using Finite Impulse Response (FIR) Filters with Custom Modulation Finite Impulse Response filters can be used to refine the transitions between symbol decision points of the generated waveforms. Figure 13-31 Filter Menu Mode > ARB Custom Modulation > Single Carrier Setup > Filter Available only when the filter selected = Root Nyquist or Nyquist page 355 Opens the IS–95 filter selection menu.
Custom Digital Modulation (Option 431) Using Finite Impulse Response (FIR) Filters with Custom Modulation The NADC and TETRA standards specify an alpha of 0.35. PDC and PHS standards specify an alpha of 0.50. For each of these standards, the Agilent X- Series signal generator provides a root Nyquist filter with the designated alphas as the default premodulation filter. Figure 13- 32 shows the Nyquist impulse response for several values of alpha.
Custom Digital Modulation (Option 431) Using Finite Impulse Response (FIR) Filters with Custom Modulation NOTE To change the filter Bbt, press Mode > Real-Time Custom Modulation > Modulation Setup > Filter > Select Gaussian > Filter Bbt. Enter a new value between 0.1 and 1. Creating a User–Defined FIR Filter Using the FIR Table Editor In this procedure, you use the FIR Values table editor to create and store an 8–symbol, windowed sync function filter with an oversample ratio of 4.
Custom Digital Modulation (Option 431) Using Finite Impulse Response (FIR) Filters with Custom Modulation Entering the Coefficient Values 1. Press the Return softkey to get to the first page of the table editor. 2. Use the cursor to highlight the Value field for coefficient 0. 3. Use the numeric keypad to type the first value (−0.000076) from Table 13- 1. As you press the numeric keys, the numbers are displayed in the active entry area. (If you make a mistake, you can correct it using the backspace key.
Custom Digital Modulation (Option 431) Using Finite Impulse Response (FIR) Filters with Custom Modulation Duplicating the First 16 Coefficients Using Mirror Table In a windowed sinc function filter, the second half of the coefficients are identical to the first half in reverse order. The signal generator provides a mirror table function that automatically duplicates the existing coefficient values in the reverse order. 1. Press Mirror Table.
Custom Digital Modulation (Option 431) Using Finite Impulse Response (FIR) Filters with Custom Modulation Figure 13-35 For details on each key, use key help as described on page 44. 2. Press Return. 3. Press Display Impulse Response. Refer to Figure 13- 36. Figure 13-36 For details on each key, use key help as described on page 44. 4. Press Return to return to the menu keys. Storing the Filter to Memory Use the following steps to store the file. 1. Press Load/Store > Store To File.
Custom Digital Modulation (Option 431) Modifying a FIR Filter Using the FIR Table Editor Figure 13-37 These keys manage the table of DMOD files in internal storage. Catalog displays FIR files that have been previously saved by the user. For details on each key, use key help as described on page 44. Memory is also shared by instrument state files and list sweep files. This filter can now be used to customize a modulation format or it can be used as a basis for a new filter design.
Custom Digital Modulation (Option 431) Modifying a FIR Filter Using the FIR Table Editor Loading the Default Gaussian FIR File Figure 13-38 Loading the Default Gaussian FIR File Mode > ARB Custom Modulation > Single Carrier Setup For details on each key, use key help as described on page 44. These softkeys select a window function (apodization function) for a filter. 1. Press Preset. 2. Press Mode > ARB Custom Modulation > Single Carrier Setup > Quick Setup > NADC. 3.
Custom Digital Modulation (Option 431) Modifying a FIR Filter Using the FIR Table Editor 5. Press Filter Symbols > 8 > Enter. 6. Press Generate. NOTE The actual oversample ratio during modulation is automatically selected by the instrument. A value between 4 and 16 is chosen dependent on the symbol rate, the number of bits per symbol of the modulation type, and the number of symbols. 7. Press Display Filter > Display Impulse Response (refer to Figure 13- 39).
Custom Digital Modulation (Option 431) Differential Encoding Refer to Figure 13- 40 on page 361. The graphic display can provide a useful troubleshooting tool (in this case, it indicates that a coefficient value is missing, resulting in an improper Gaussian response). 4. Press Return. 5. Highlight coefficient 15. 6. Press 1 > Enter. Storing the Filter to Memory The maximum file name length is 23 characters (alphanumeric and special characters). 1. Press Return > Load/Store > Store To File. 2.
Custom Digital Modulation (Option 431) Differential Encoding The following illustration shows a 4QAM modulation I/Q State Map. 2nd Symbol Data = 00000001 Distinct values: –1, +1 1st Symbol Data = 00000000 Distinct values: +1, +1 2 1 3 4 3rd Symbol Data = 00000010 Distinct values: –1, –1 4th Symbol Data = 00000011 Distinct values: +1, –1 Differential encoding employs relative offsets between the states in the symbol table to encode user–defined modulation schemes.
Custom Digital Modulation (Option 431) Differential Encoding Table 13-2 Data Offset Value 00000010 +2 00000011 0 NOTE The number of bits per symbol can be expressed using the following formula. Because the equation is a ceiling function, if the value of x contains a fraction, x is rounded up to the next whole number. Where x = bits per symbol, and y = the number of differential states.
Custom Digital Modulation (Option 431) Differential Encoding These symbol table offsets will result in one of the transitions, as shown.
Custom Digital Modulation (Option 431) Differential Encoding 1st 1st Symbol 3rd Symbol { { { 2nd 5th Symbol 4th Symbol 2nd Symbol 5th 3rd { { Data = 0011100001 4th Data Value 00 01 10 11 Symbol Table Offset +1 –1 +2 +0 As you can see from the previous illustration, the 1st and 4th symbols, having the same data value (00), produce the same state transition (forward 1 state).
Custom Digital Modulation (Option 431) Differential Encoding This loads a default 4QAM I/Q modulation and displays it in the I/Q table editor. The default 4QAM I/Q modulation contains data that represent 4 symbols (00, 01, 10, and 11) mapped into the I/Q plane using 2 distinct values (1.000000 and −1.000000). These 4 symbols will be traversed during the modulation process by the symbol table offset values associated with each symbol of data. Refer to Figure 13- 41.
Custom Digital Modulation (Option 431) Differential Encoding Editing the Differential State Map 1. Press 1 > Enter. This encodes the first symbol by adding a symbol table offset of 1. The symbol rotates forward through the state map by 1 value when a data value of 0 is modulated. 2. Press +/– > 1 > Enter. This encodes the second symbol by adding a symbol table offset of −1. The symbol rotates backward through the state map by 1 value when a data value of 1 is modulated.
14 Multitone and Two–Tone Waveforms (Option 430) Before using this information, you should be familiar with the basic operation of the signal generator. If you are not comfortable with functions such as setting the power level and frequency, refer to Basic Operation on page 43 and familiarize yourself with the information in that chapter. This feature is available only in Agilent X- Series vector signal generators with Option 430. Option 430 requires Option 653 or 656.
Multitone and Two–Tone Waveforms (Option 430) Using Two–Tone Modulation • Changing the Alignment of a Two–Tone Waveform on page 373 See also: Saving a Waveform’s Settings & Parameters on page 155 NOTE For more information about two–tone waveform characteristics, and the two–tone standard, download Application Note 1410 from our website by going to http://www.agilent.com and searching for “AN 1410” in Test & Measurement.
Multitone and Two–Tone Waveforms (Option 430) Using Two–Tone Modulation 4. Press Mode > More > Two–Tone > Freq Separation > 10 > MHz. 5. Press Two Tone Off On to On. 6. Turn on the RF output. The two–tone signal is now available at the signal generator RF OUTPUT connector. Figure 14- 1 on page 371 shows what the signal generator display should look like after all steps have been completed.
Multitone and Two–Tone Waveforms (Option 430) Using Two–Tone Modulation Figure 14-2 Two–Tone Channels Intermodulation Distortion For details on each key, use key help as described on page 44. Carrier Feedthrough Carrier Feedthrough Distortion Minimizing Carrier Feedthrough This procedure describes how to minimize carrier feedthrough and measure the difference in power between the tones and their intermodulation distortion products.
Multitone and Two–Tone Waveforms (Option 430) Using Two–Tone Modulation 8. Create a marker and place it on the peak of one of the two tones. 9. Create a delta marker and place it on the peak of the adjacent intermodulation product, which should be spaced 10 MHz from the marked tone. 10. Measure the power difference between the tone and its distortion product. You should now see a display that is similar to the one shown in Figure 14- 3 on page 373.
Multitone and Two–Tone Waveforms (Option 430) Using Two–Tone Modulation NOTE Whenever a change is made to a setting while the two–tone generator is operating (Two Tone Off On set to On), you must apply the change by pressing the Apply Settings softkey before the updated waveform will be generated. When you apply a change, the baseband generator creates a two–tone waveform using the new settings and replaces the existing waveform in ARB memory. 3.
Multitone and Two–Tone Waveforms (Option 430) Using Multitone Modulation Using Multitone Modulation Multitone Modulation Softkeys This softkey is active if changes have been made to the current Multitone waveform in the table editor. The softkey must be pressed to apply those changes. page 375 page 376 page 377 page 377 Active when Multitone enabled. For softkey usage, see page 146 page 146 see page 147 (Multitone’s ARB Setup is similar to Dual Arb Setup.
Multitone and Two–Tone Waveforms (Option 430) Using Multitone Modulation Figure 14-5 The Random Seed softkey that affects the Multitone’s phase values is not used in the following examples and is shown for reference, only. For details on each key, use key help as described on page 44. 5. Press Done. You now have a multitone setup with five tones spaced 20 kHz apart. The center tone is placed at the carrier frequency, while the other four tones are spaced in 20 kHz increments from the center tone.
Multitone and Two–Tone Waveforms (Option 430) Using Multitone Modulation 2. Set the output amplitude to 0 dBm. 3. Press RF On/Off. The multitone waveform is now available at the signal generator’s RF OUTPUT connector. Applying Changes to an Active Multitone Signal If the multitone generator is currently in use (Multitone Off On set to On) while changes are made in the Multitone Setup table editor, you must apply the changes before the updated waveform will be generated.
Multitone and Two–Tone Waveforms (Option 430) Using Multitone Modulation Recalling a Multitone Waveform Using this procedure, you learn how to recall a multitone waveform from the signal generator’s memory catalog. If you have not created and stored a multitone waveform, complete the steps in the previous sections, Creating a Custom Multitone Waveform on page 369 and Storing a Multitone Waveform on page 377, then preset the signal generator to clear the stored multitone waveform from volatile ARB memory.
15 Working in a Secure Environment If you are using the instrument in a secure environment, you may need details of how to clear or sanitize its memory, in compliance with published security standards of the United States Department of Defense, or other similar authorities. For the Series B MXG and EXG instruments, this information is contained in the PDF document "Security Features and Document of Volatility".
Working in a Secure Environment Using Secure Display Using Secure Display This function prevents unauthorized personnel from reading the instrument display or tampering with the current configuration via the front panel. When Secure Display is active, the display is blank, except for an advisory message, as shown in Figure 15- 1 below. All front panel keys are disabled. To set Secure Display, press: Utility > Display > More > Activate Secure Display > Confirm Secure Display.
16 Troubleshooting • Display on page 382 • Signal Generator Lock–Up on page 382 • RF Output on page 382 — — — — — — — No RF Output Power Supply Shuts Down No Modulation at the RF Output RF Output Power too Low Distortion Signal Loss While Working with a Spectrum Analyzer Signal Loss While Working with a Mixer • Sweep on page 386 — — — — — Cannot Turn Off Sweep Sweep Appears Stalled Incorrect List Sweep Dwell Time List Sweep Information is Missing from a Recalled Register Amplitude Does Not Change in Li
Troubleshooting Display Display The Display is Too Dark to Read Brightness may be set to minimum. Use the figure in “Display Settings” on page 28 to locate the brightness softkey and adjust the value so that you can see the display. The Display Turns Black when Using USB Media Removing the USB media when the instrument begins to use it can cause the screen to go black. Cycle instrument power.
Troubleshooting RF Output RF Output Power too Low • If the AMPLITUDE area of the display shows the OFFS indicator, eliminate the offset: Press Amptd > More 1 of 2 > Amptd Offset > 0 > dB. See also “Setting an Output Offset” on page 122. • If the AMPLITUDE area of the display shows the REF indicator, turn off the reference mode: 1. Press Amptd > More > Amptd Ref Off On until Off highlights. 2. Reset the output power to the desired level. See also “Setting an Output Reference” on page 123.
Troubleshooting RF Output Signal Loss While Working with a Mixer CAUTION To avoid damaging or degrading the performance of the signal generator, do not exceed 33 dBm (2W) maximum of reverse power levels at the RF input. See also Tips for Preventing Signal Generator Damage on www.agilent.com. To fix signal loss at the signal generator’s RF output during low–amplitude coupled operation with a mixer, add attenuation and increase the RF output amplitude.
Troubleshooting RF Output The solution at right shows a similar configuration with the addition of a 10 dB attenuator connected between the RF output of the signal generator and the input of the mixer. The signal generator’s ALC level increases to +2 dBm and transmits through a 10 dB attenuator to achieve the required −8 dBm amplitude at the mixer input.
Troubleshooting Sweep Sweep Cannot Turn Off Sweep Press Sweep > Sweep > Off. Sweep Appears Stalled The current status of the sweep is indicated as a shaded rectangle in the progress bar (see “Configuring a Swept Output” on page 50). If the sweep appears to stall, check the following: 1. Turn on the sweep with one of the following key sequences: Sweep > Sweep > Freq Sweep > Sweep > Amptd Sweep > Sweep > Waveform (vector instruments only) 2. If the sweep is in single mode, press the Single Sweep softkey. 3.
Troubleshooting Internal Media Data Storage Internal Media Data Storage Instrument State Saved but the Register is Empty or Contains the Wrong State If the register number you intended to use is empty or contains the wrong instrument state, recall register 99. If you selected a register number greater than 99, the signal generator automatically saves the instrument state in register 99. See also “Working with Instrument State Files” on page 68.
Troubleshooting Error Messages Error Messages Error Message Types Events do not generate more than one type of error. For example, an event that generates a query error does not generate a device–specific, execution, or command error. Query Errors (–499 to –400) indicate that the instrument’s output queue control has detected a problem with the message exchange protocol described in IEEE 488.2, Chapter 6. Errors in this class set the query error bit (bit 2) in the event status register (IEEE 488.
Troubleshooting Front Panel Tests Front Panel Tests Set all display pixels to the selected color. To return to normal operation, press any key. Blink RF On/Off, Mod on/Off, and More LEDs Displays a keyboard map. As you press a key, the map indicates the key location. Correct operation: Full CCW = –10 Full CW = 10 For details on each key, use key help as described on page 44.
Troubleshooting Self Test Overview Self Test Overview The self test is a series of internal tests that checks different signal generator functions. The self test, is also available by via the remote web interface. For more information on the Web- Enabled MXG, refer to the Programming Guide.
Troubleshooting Self Test Overview Utility > Instrument Info Automatically runs diagnostic self test. Self Test Summary displays current status. Opens a table in which user selects specific tests and view details in Test Editor display. Displays detailed information of highlighted test. Refer to page 44 Executes highlighted operation. Selects or deselects highlighted operation. Selects or deselects all operations. Executes all selected operations.
Troubleshooting Self Test Overview 392 Agilent X-Series Signal Generators User’s Guide
Troubleshooting Licenses Licenses A Time–Based License Quits Working • The instrument’s time or date may have been reset forward causing the time–based license to expire. • The instrument’s time or date may have been reset backward more than approximately 25 hours, causing the instrument to ignore time–based licenses. See page 30 for details and cautions on setting time and date.
Troubleshooting Contacting Agilent Technologies 394 Agilent X-Series Signal Generators User’s Guide
Glossary A F Active Entry The currently selected, and therefore editable, entry or parameter ARB Arbitrary waveform generator AWG Arbitrary waveform generator. Additive white Gaussian noise B BBG Media Baseband generator media. Volatile memory, where waveform files are played or edited. BNC Connector Bayonet Neill- Concelman connector. A type of RF connector used to terminate coaxial cable. C CCW Counterclockwise C/N Carrier- to- noise ratio CW Continuous wave.
stored. equals zero at all symbol times except the center (desired) one. P IP Internet protocol. The network layer for the TCP/IP protocol suite widely used on Ethernet networks. L Persistent That which is unaffected by preset, user preset, or power cycle. LAN Local area network Point- to- point Time In a step sweep (page 52), the sum of the dwell time, processing time, switching time, and settling time. LO Local oscillator R LXI LAN eXtension for Instrumentation.
peak value. S Softkey A button located along the instrument’s display that performs whatever function is shown next to it on that display. T TCP Transmission control protocol. The most common transport layer protocol used on Ethernet and the Internet. Terminator A unit indicator (such as Hz or dBm) that completes an entry. For example, for the entry 100 Hz, Hz is the terminator. Type- N Connector Threaded RF connector used to join coaxial cables. U USB Universal serial bus. See also http://www.usb.
398 Agilent X-Series Signal Generators User’s Guide
Index Symbols , 214 ΦM annunciator, 10 dc offset, removing, 79 hardkey, 75 softkeys, 75, 79 # points softkey, 53 # Skipped Points softkey, 166 Numerics 10 MHz OUT connector, 15, 25, 26 100Base- T LAN cable, 33 128 QAM softkey, 319, 323, 325, 326, 327, 328, 329, 333 1410, application note, 370 16- Lvl FSK softkey, 319, 323, 325, 326, 327, 328, 329, 333 16QAM softkey, 319, 323, 325, 326, 327, 328, 329, 333 2’s complement description, 274, 289 256 QAM softkey, 319, 323, 325, 326, 327, 328, 329, 333 2- Lvl FSK
Index ASK softkey, 319, 323, 325, 326, 327, 328, 329, 333 ATTEN HOLD annunciator, 10 Atten/ALC Control softkey, 47, 49 Auto softkeys (DHCP/Auto- IP), 33 Auto, 94, 118 Recall, 128 AUTOGEN_WAVEFORM file, 316 auto- IP, 33 Auto- IP softkey, 33 Automatically Use USB Media If Present softkey, 62 AUX I/O connector, 18 Auxiliary Software Options softkey, 40 AWGN adding, 245, 10 definition, 395, 245 softkeys, 251 AWGN softkeys, 246, 247, 248, 249 system, 228 trigger setup, 228 BbT, 395 BERT, 291 Binary softkey, 62
Index Error Queue(s), 73 Header, 155 Text, 45 clipping circular, 189, 192 rectangular, 190, 193 softkeys, 185 clock adjustment phase and skew, 264 clock gate, 292 clock rate limits, logic type output, 254 clock source setting, 277, 285 clock timing parallel data, 259, 262, 264 serial data, 264 clock, sample rate, 18 clocking, frequency reference, 257 clocking, frequency reference diagrams, 258 clocks per sample parallel data, 259, 262 coefficient values, entering, 215, 356 color palette, display, 28 comment
Index system, restoring, 44 Default softkey, 318, 322 delay I/Q, 208 multiple BBG sync, 228 Delete softkeys All Regs in Seq, 68, 148, 62, 68, 128, 151, 175 File, 62, 64, 67, 72 Item, 55 Row, 55 Selected Waveform, 151, 175, 68 Waveform Sequence, 175 description & plots, phase noise, 311 DETHTR annunciator, 11 device clock source selection, 277, 285 Device softkey, 47, 49 DHCP, 33, 395 DHCP softkey, 33 diagram data types, 268 diagrams clock timing parallel data, 259, 262, 264 serial data, 264 , 258 Diff Mode
Index Erase All, 379 Erase and Sanitize All, 379 ERR annunciator, 11 Error hardkey, 73 error messages, 73 DAC over range, 195, 200 display area, 12 message format, 73 types, 388 Esc hardkey, 7 EVENT connector, AUX I/O, 18, 17, 161 output jitter, 177, 161 EVM, 395 EVM error, 143 example Waveform license, Opt 25x adding a waveform, 242 locking a slot, 242 examples FIR filters creating, 215, 353, 355 modifying, 220, 359 LF output, configuring, 81 Execute Cal softkey, 210 EXT CLOCK connector, 17 EXT REF annunci
Index hardkey, 75 softkeys, 75 formula, skew discrete steps, 264 Free Run softkey, 51, 126, 179 Free- Run softkey, 130 Freq Dev softkey, 319, 323, 325, 326, 327, 328, 329, 333 FREQ hardkey, 47, 49 Freq softkeys, 98 frequency display area, 10 hardkey, 8, 47, 49 LF output, 82 start and stop, swept- sine, 83 modulation, 75, 124 offset, 122, 200 reference, 123 setting, 47, 49, 47, 49 frequency output limits, clock rates & logic levels, 254 frequency reference common, 257 hookup diagrams, 258 frequency units, 47
Index interface GPIB, 32 LAN, 33 internal reference oscillator, using, 31 Internal Baseband Adjustments softkey, 208 internal clock source selection, 277, 285 internal media, 72 Internal Storage to USB softkey, 67 Internal/USB Storage Selection softkey, 62 interpolator filter, 195 IP Address softkey, 33 address, setting, 33 definition, 396 IQ clock rates, 255 IQ map, QAM modulation, 363 J jitter on EVENT output, 177 K keyboard, using, 128 keys disabling, 379 front panel, 5 help on, 44 numeric, 6 test, 389
Index markers, aligning signal, 162 markers, waveform, 161–177 media BBG, 395 erasing, 379 Flash Drive, 72 int, 395 storage, 72 types, 146, 379 USB, 72, 387 memory erasing data from, 379 See also media menu keys, 6 messages, error, 388 messages, warning Opt 25x Licensing, 244 mirror table, duplicating coefficients, 217, 357 mixer, troubleshooting signal loss, 384 Mod On/Off hardkey, 7, 59, 60 Mod On/Off, Option UNT, 75 Mod Type Softkeys, 319, 323, 325, 326, 327, 328, 329, 333 Mode hardkey, 147, 246, 247, 24
Index O OFFS annunciator, 11 offset, 143 offset binary use, 274, 289 offsets baseband frequency, 200 I/Q, 208 output, using, 122 on/off switch, 9 operation modes of, 4 operation, basic, 43 operation, remote, 32 optimization, I/Q, 142, 205 option 430 multitone mode, 375 two tone mode, 369 Option U01, 106 internal channel correction, 106 Option UNT Mod On/Off hardkey, 75 options 651/652/654 description, 4 multitone mode, 375 two- tone mode, 369 enabling, 27, 39 resource, 3 UNT, 4 Options 250- 259, 237 Options
Index using, 44 Preset softkeys Language, 29, 55, 98 Preset, 29 Prev REG softkey, 128 Prev SEQ softkey, 128 Proceed With Reconfiguration softkey, 33, 34 programming guide content, xiii protection, DAC over range baseband offset frequency, 202 phase noise impairment, 314 PSK softkey, 319, 323, 325, 326, 327, 328, 329, 333 pulse annunciator, 11 characteristics, 131, 14, 24 marker, viewing, 171, 129 narrow, 119 sync signal, 52 video signal, 52 Pulse hardkey, 130 pulse modulation, 4 Pulse softkeys, 52, 130 Puls
Index output configuring, 48, 7 leveling, external, 110–117 troubleshooting, 382 RF During Power Search softkey, 94, 118 RF Output softkey, 205, 206 RFC NETBIOS Naming softkey, 33 ringing, 195 ripple, 195 RMS, 396 RMS softkey, 94, 118 Rohde & Schwarz softkey, 35, 37 roort, 396 root cosine filter.
Index definition of, 397 help on, 44 label area, 12, 6 See also specific key source settled signal, 52 Source Settled softkey, 52, 130 Span softkey, 94, 118 special pattern ignore function, 301 Specify Default Storage Path for User Media softkey, 62 spectral regrowth, 188 spectrum analyzer, troubleshooting signal loss, 383 square root raised cosine filter.
Index U W unfiltered & filtered samples, 274, 289 UNLEVEL annunciator, 11 unleveled operation, 118 UNLOCK annunciator, 11 Unspecified softkey, 155 UNT, option, 4 UNU, option, 4 UNW, option, 4 Up Directory softkey, 62, 64, 67 Update in Remote softkey, 28 urls, 3, 31, 39, 393 USB connecting media, 72 definition, 397, 15, 25 host connector, 5, 15, 25 keyboard, using, 128 softkeys File Manager, 62, 63 Keyboard Control, 128 to BBG Memory softkey, 67, 387 Use softkeys As, 66 Current Directory As Default Path, 6
Index 412 Agilent X-Series Signal Generators User’s Guide
