POWER SENSOR MANUAL Revision Date: 4/26/11 Manual P/N 98501900M CD P/N 98501999M BOONTON ELECTRONICS 25 EASTMANS ROAD PARSIPPANY, NJ 07054 Web Site: www.boonton.com Email: boonton@boonton.
SAFETY SUMMARY The following general safety precautions must be observed during all phases of operation and maintenance of this instrument. Failure to comply with these precautions or with specific warnings elsewhere in this manual violates safety standards of design, manufacture, and intended use of the instruments. Boonton Electronics Corporation assumes no liability for the customer's failure to comply with these requirements. THE INSTRUMENT MUST BE GROUNDED.
Contents Paragraph Power Sensor Manual Page 1 Introduction 1-1 Overview 1-2 Sensor Trade-offs 1-3 Calibration and Traceability 1 1 1 3 2 Power Sensor Characteristics 5 3 Power Sensor Uncertainty Factors 17 4 Low Response and Standing-Wave-Ratio (SWR) Data 28 5 Pulsed RF Power 5-1 Pulsed RF Power Operation 5-2 Pulsed RF Operation Thermocouple Sensors 5-3 Pulsed RF Operation Diode Sensors 32 32 33 34 6 Calculating Measurement Uncertainty 6-1 Measurement Accuracy 6-2 Uncertainty Contribution
Figures Figure Page 1-1 1-2 1-3 Error Due to AM Modulation (Diode Sensor) Linearity Traceability Calibration Factor Traceability 2 3 4 4-1 4-2 4-3 4-4 4-5 4-6 4-7 4-8 4-9 4-10 Model 51071 Low Frequency Response Model 51072 Low Frequency Response Model 51075 Low Frequency Response Model 51071 SWR Data Model 51072 SWR Data Model 51075 SWR Data Model 51078 SWR Data Model 51100 SWR Data Model 51101 SWR Data Model 51102 SWR Data 28 28 29 29 29 30 30 30 31 31 5-1 5-2 5-3 Pulsed RF Operation Pulsed Accura
Tables (con't.) Table 3-1 3-1 3-1 3-2 3-2 3-2 3-2 3-3 Power Sensor Manual Page Diode & Thermocouple Power Sensor Calibration Factor Uncertainty (con't.) Models 51085, 51086, 51087 Diode & Thermocouple Power Sensor Calibration Factor Uncertainty (con't.) Models 51081, 51100(9E), 51101, 51102, 51200, 51201 Diode & Thermocouple Power Sensor Calibration Factor Uncertainty (con't.
1 Introduction 1-1 Overview The overall performance of a power meter is dependent upon the sensor employed. Boonton Electronics (Boonton) has addressed this by providing quality power sensors to meet virtually all applications. Boonton offers a family of sensors with frequency ranges spanning 10 kHz to 100 GHz and sensitivity from 0.1 nW (-70 dBm) to 25 W (+44 dBm). A choice of Diode or Thermocouple Sensors with 50 or 75 ohms impedances in Coaxial or Waveguide styles are available.
This non-square-law region may be "shaped" with meter corrections, but only for one defined waveform, such as a CW signal. By incorporating "shaping", also referred to as "Linearity Calibration", Boonton offers a dynamic range from 0.1 nW (-70 dBm) to 100 mW (+20 dB) with a single sensor module.
1-3 Calibration and Traceability Boonton employs both a linearity calibration as well as a frequency response calibration. This maximizes the performance of Diode Sensors and corrects the non-linearity on all ranges. Linearity calibration can be used to extend the operating range of a Diode Sensor. It can also be used to correct non-linearity throughout a sensor's dynamic range, either Thermocouple or Diode. A unique traceability benefit offered is the use of the 30 MHz working standard.
Power sensors have response variations (with respect to the reference frequency) at high frequencies. Calibration factors ranging from ± 3 dB are entered into the instrument memories at the desired frequencies. Generally, calibration factors are within ±0.5 dB. These calibration factors must be traceable to the National Institute of Standards Technology (NIST) to be meaningful.
2 Power Sensor Characteristics The power sensor has three primary functions. First the sensor converts the incident RF or microwave power to an equivalent voltage that can be processed by the power meter. The sensor must also present to the incident power an impedance which is closely matched to the transmission system. Finally, the sensor must introduce the smallest drift and noise possible so as not to disturb the measurement.
5107xA Series of RF Sensors The “A” series sensors were created to improve production calibration results. These sensors possess the same customer specifications as the non-A types (i.e.: 51075 and 51075A), however, the utilization of new calibration methods enhances the testing performance over previous techniques. In doing this, Boonton can provide the customer with a better product with a higher degree of confidence.
Table 2-1. Diode and Thermal CW Sensor Characteristics (con't.) Model Frequency Range Dynamic Range (1) Overload Rating Impedance Peak Power RF Connector CW Power (dBm) Maximum SWR Drift and Noise @ 0 dBm Lowest Range Noise Drift (typ.) Frequency SWR 1 Hour (GHz) RMS 2σ (typical) WIDE DYNAMIC RANGE DUAL DIODE SENSORS 51085 500 kHz -30 to +20 1kW for 5µs to 4 1.15 2 uW 50 Ω to 18 GHz (2) 5W to 12.4 1.20 (7,10) (see notes below) to 18 1.25 N(M) 51086 0.
Table 2-1. Diode and Thermal CW Sensor Characteristics (con't.) Frequency Range Model Dynamic Range (1) Impedance Overload Rating @ 0 dBm Lowest Range Peak Power RF Connector CW Power (dBm) Drift and Noise Maximum SWR Drift (typ.) Frequency (GHz) SWR Noise 1 Hour RMS (typical) 2σ 100 nW 200 nW 100 nW 200 nW 100 nW 200 nW 10 µW 20 µW 10 µW 20 µW 25 µW 50 µW 25 µW 50 µW THERMOCOUPLE SENSORS 51100 (9E) 50 Ω N(M) 10 MHz to 18 GHz 51101 50 Ω N(M) 100 kHz to 4.
Table 2-2. Peak Power Sensor Characteristics Frequency Power Range Measurement Model Peak CW (1) Impedance RF Connector (GHz) Int.
Table 2-2. Peak Power Sensor Characteristics (con't.) Frequency Power Range Measurement Model Peak CW (1) Impedance RF Connector (GHz) Int. Trigger (dBm) Overload Rating Maximum SWR Rise Time Fast @ 0 dBm Drift & Noise Slow Peak Power High Low Frequency CW Power Bandwidth (ns) Bandwidth (ns) (GHz) SWR Peak Power CW Power DUAL DIODE PEAK POWER SENSORS Sensors below are for use with 4400, 4500, 4400A, 4500A and 4530. Compatible with 4530 Series internal 50 MHz calibrator. 57318 50 Ω 0.
Table 2-2. Peak Power Sensor Characteristics (con't.) Frequency Power Range Measurement Model Overload Rating Maximum SWR Rise Time Peak @ 0 dBm Fast Slow Impedance High BW CW Peak Power High Low Frequency RF Connector Low BW (GHz) Int. Trigger (dBm) CW Power Bandwidth (ns) Bandwidth (ns) (GHz) SWR Drift & Noise Peak Power CW Power DUAL DIODE PEAK POWER SENSORS Sensors below are for use with model 4500B ONLY. 58318 50 Ω 0.
Sensor characteristics of Boonton legacy sensors are presented in tables 2-3 (CW) and 2-4 (Waveguide). This data is presented for reference only. Contact the sales department for availability. Table 2-3. Legacy Diode CW Sensor Characteristics Model Frequency Range Impedance Dynamic Range Overload Rating (1) (3) Peak Power RF Connector CW Power (dBm) Maximum SWR Drift and Noise @ 0 dBm Lowest Range Noise Drift (typ.
Table 2-3. Legacy Diode CW Sensor Characteristics (con't.) Frequency Range Model Impedance Dynamic Range Overload Rating (1) Peak Power RF Connector CW Power (dBm) Maximum SWR Drift and Noise Lowest Range @ 0 dBm Noise Drift (typ.) Frequency SWR 2σ 1 Hour RMS (2) (typical) 65 nW 130 nW 200 pW 400 pW 200 pW 400 pW (GHz) DUAL DIODE SENSORS 51078 50 Ω 100 kHz -20 to +37 100 W for 1µs to 4 1.15 150 nW to 18 GHz (3) (8) 7W to 12 1.25 (6) to 18 1.
Table 2-4. Legacy Waveguide Sensor Characteristics Model Frequency Range Dynamic Range Impedance (Ref. Freq.) (2) RF Connector Overload Rating Maximum SWR Drift and Noise @ 0 dBm Lowest Range Noise Drift CW Power (dBm) Frequency SWR (GHz) RMS after 2 hr. (/hr) (typical) 2σ WAVEGUIDE SENSORS 51035 (4K) 18 GHz -50 to +10 WR-42 to 26.5 GHz (1) 51036 (4KA) 26.5 GHz -50 to +10 WR-28 to 40 GHz (1) 51037 (4Q) 33 GHz WR-22 to 50 GHz 100 mW 18 to 26.5 1.
Table 2-4. Legacy Waveguide Sensor Characteristics (con't.) Model Frequency Range Dynamic Range Impedance (Ref. Freq.) (2) RF Connector Overload Rating Maximum SWR Drift and Noise @ 0 dBm Lowest Range Noise Drift CW Power (dBm) Frequency SWR (GHz) RMS after 2 hr.
Sensor characteristics of Boonton legacy Peak Power Sensors are presented in table 2-5. This data is presented for reference only. Contact the sales department for availability. Table 2-5. Legacy Peak Power Sensor Characteristics Frequency Power Range Measurement Model Peak CW (1) Impedance RF Connector (GHz) Int.
3 Power Sensor Uncertainty Factors The uncertainty factors, as a function of frequency for the Diode and Thermocouple, Peak and Waveguide sensors, are listed in Tables 3-1, 3-2 and 3-3 respectively. These values represent typical results based on factory test data unless otherwise noted.
Table 3-1. Diode and Thermocouple Power Sensor Calibration Factor Uncertainty (con't.) Models 51071, 51072, 51075, 51077, 51078, 51079 Model Freq GHz 51071 % % RSS 51072 % % RSS 51075 % % RSS 51077 % % RSS 51078 % 51079 % RSS % % RSS 3.3 3.0 3.1 3.1 3.2 3.2 3.2 2.9 3.1 4.8 5.4 5.5 5.2 5.8 6.1 6.5 6.5 5.7 6.2 2.3 2.2 2.2 2.3 2.3 2.3 2.3 2.2 2.2 4.0 4.2 4.3 4.2 5.2 5.3 5.5 5.5 5.2 5.3 WIDE DYNAMIC RANGE DUAL DIODE SENSORS 0.
Table 3-1. Diode and Thermocouple Power Sensor Calibration Factor Uncertainty (con't.) Models 51071A, 51072A, 51075A, 51077A, 51078A, 51079A Freq GHz Model 51071A % % RSS 51072A % % RSS 51075A % % RSS 51077A % % RSS 51078A % % RSS 51079A % % RSS 3.3 3.0 3.1 3.1 3.2 3.2 3.2 2.9 3.1 4.8 5.4 5.5 5.2 5.8 6.1 6.5 6.5 5.7 6.2 2.3 2.2 2.2 2.3 2.3 2.3 2.3 2.2 2.2 4.0 4.2 4.3 4.2 5.2 5.3 5.5 5.5 5.2 5.3 WIDE DYNAMIC RANGE DUAL DIODE SENSORS 0.
Table 3-1. Diode and Thermocouple Power Sensor Calibration Factor Uncertainty (con't.) Models 51085, 51086, 51087 Model Freq GHz 51085 % % RSS 51086 % % RSS 51087 % % RSS % % RSS % % RSS % % RSS WIDE DYNAMIC RANGE DUAL DIODE SENSORS 0.03 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 26.5 27 28 29 30 31 32 33 34 35 36 37 38 39 40 20 2.0 1.8 2.0 2.1 2.2 2.4 2.5 2.3 2.5 3.5 4.0 4.3 4.4 3.7 3.5 4.2 4.0 3.3 3.8 1.1 1.0 1.1 1.2 1.3 1.4 1.5 1.5 1.6 2.3 2.8 3.0 3.2 2.6 2.3 2.
Table 3-1. Diode and Thermocouple Power Sensor Calibration Factor Uncertainty (con't.) Models 51081, 51100(9E), 51101, 51102, 51200, 51201 Freq 51081 Model (Alias) 51101 51102 51100 51200 51201 (9E) GHz % % RSS % % RSS % % RSS % % RSS % % RSS % % RSS 1.4 1.0 1.0 1.0 1.3 1.3 1.3 1.5 1.6 2.0 2.3 2.5 2.2 2.1 2.4 2.6 2.8 2.2 2.8 2.6 2.3 2.4 3.0 3.1 1.5 1.4 1.4 2.1 2.1 DIODE AND THERMOCOUPLE SENSORS 0.03 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 26.
Table 3-1. Diode and Thermocouple Power Sensor Calibration Factor Uncertainty (con't.) Models 51300, 51301, 51082 Model Freq GHz 51300 % % RSS 51301 % % RSS GHz THERMOCOUPLE 0.03 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 2.5 1.7 1.9 1.9 2.3 2.3 2.3 2.3 2.6 3.2 3.5 3.8 3.4 3.2 3.6 3.8 4.1 3.4 4.1 1.4 1.0 1.0 1.0 1.3 1.3 1.3 1.5 1.6 2.0 2.3 2.5 2.2 2.1 2.4 2.6 2.8 2.2 2.8 2.4 2.9 2.7 2.6 2.9 Model 51082 Freq % % RSS DIODE 1.3 2.0 1.7 1.6 1.9 0.05 40 41 42 43 44 45 46 47 48 49 50 2.0 10.
Table 3-2. Peak Power Sensor Calibration Factor Uncertainty Models 56218, 56226, 56318, 56326, 56340, 56418 Model Freq GHz 56218 % % RSS 56226 % % RSS 56318 % % RSS 56326 % % RSS 56340 % 56418 % RSS % % RSS 2.2 1.7 1.9 2.1 2.2 2.3 2.4 2.6 2.8 4.1 4.1 4.1 4.2 4.3 4.6 4.8 4.9 5.0 5.1 5.8 6.3 6.7 6.8 6.6 6.3 6.3 6.4 1.5 1.1 1.2 1.4 1.5 1.6 1.7 2.0 2.2 3.6 3.8 4.0 3.9 3.9 4.1 4.1 4.2 4.2 4.2 5.0 5.6 5.9 5.8 5.4 4.9 4.9 4.9 1.7 1.6 2.0 2.1 2.1 2.4 2.2 1.7 1.8 2.7 3.3 3.5 3.4 3.2 3.3 3.5 3.9 3.
Table 3-2. Peak Power Sensor Calibration Factor Uncertainty (con't.) Models 56518, 56526, 56540, 56006, 57006 Freq GHz 56518 % % RSS Model 56540 56526 % % RSS % % RSS 56006 (1) 57006 (1) % % % RSS 2.8 2.8 2.8 3.0 3.3 3.4 3.3 1.4 1.4 1.4 1.5 1.5 1.5 1.5 % RSS DUAL DIODE PEAK POWER SENSORS 0.5 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 26.5 27 28 29 30 31 32 33 34 35 36 37 38 39 40 24 1.2 1.3 1.6 1.7 1.6 2.0 2.1 1.8 1.9 2.6 2.9 3.7 3.7 3.1 3.4 3.6 3.8 3.6 3.7 0.
Table 3-2. Peak Power Sensor Calibration Factor Uncertainty (con't.) Models 57318, 57340, 57518, 57540, 58318, 59318 Model Freq GHz 57318 % % RSS 57340 % % RSS 57540 57518 % % RSS % % RSS 58318 (1) 59318 (1) % % % RSS % RSS DUAL DIODE PEAK POWER SENSORS 0.5 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 26.5 27 28 29 30 31 32 33 34 35 36 37 38 39 40 1.6 1.7 2.0 2.1 2.0 2.2 2.3 1.9 1.9 2.5 3.2 3.6 3.1 2.8 3.5 3.8 3.8 3.2 3.5 1.1 1.1 1.3 1.5 1.3 1.5 1.7 1.4 1.2 1.7 2.
Table 3-2. Peak Power Sensor Calibration Factor Uncertainty (con't.) Models 59340 Model Freq GHz 59340 % % RSS % % RSS % % RSS % % RSS % % RSS % % RSS DUAL DIODE PEAK POWER SENSORS 0.5 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 26.5 27 28 29 30 31 32 33 34 35 36 37 38 39 40 26 2.5 1.9 2.0 2.2 2.4 2.5 2.7 3.0 3.2 4.7 4.8 4.9 4.9 5.1 5.3 5.1 4.9 4.6 4.5 4.7 4.9 5.3 5.9 6.1 6.3 6.3 6.5 6.9 7.4 6.6 6.4 6.3 6.5 6.9 7.3 6.6 6.5 5.7 4.9 5.6 6.4 6.6 1.7 1.3 1.3 1.5 1.7 1.
Table 3-3. Waveguide Sensor Calibration Factor Uncertainty Models 51035(4K), 51036(4KA), 51037(4Q), 51045(4U), 51046(4V), 51047(4W), 51942(WRD-180) Reference Frequency Model (Alias) GHz WAVEGUIDE at Reference Frequency % % RSS Over Sensor Bandwidth % % RSS SENSORS 51035 (4K) 22 6 5 6 5 51036 (4KA) 33 6 5 10 7 51037 (4Q) 40 10 6 13 7 51045 (4U) 40 10 6 13 8 51046 (4V) 60 12 6 13 9 51047 (4W) 94 12 9 13 11 51942 (WRD-180) 33 6 5 10 7 Denotes legacy sensors.
4 Low Frequency Response and Standing-Wave-Ratio (SWR) Data The typical performance data that follows is not guaranteed, however, it represents a large number of production units processed. Therefore, it is a good guideline for user expectations. The worst case specifications are quite conservative in accordance with Boonton's general policy.
Response (dB) 0.0 0 dBm -0.5 -1.0 -40 dBm -1.5 -2.0 -2.5 0.1 0.3 Frequency (MHz) 1 Figure 4-3. Model 51075 Low Frequency Response 2.0 SWR 1.8 Spec 1.6 1.4 1.2 1.0 5 10 15 Frequency (GHz) 20 25 Figure 4-4. Model 51071 SWR Data 2.0 SWR 1.8 Spec 1.6 1.4 1.2 1.0 5 10 15 20 25 Frequency (GHz) 30 35 Figure 4-5.
2.0 SWR 1.8 1.6 Spec 1.4 1.2 1.0 5 10 15 Frequency (GHz) 20 25 Figure 4-6. Model 51075 SWR Data 2.0 SWR 1.8 1.6 Spec 1.4 1.2 1.0 5 10 15 Frequency (GHz) 20 25 Figure 4-7. Model 51078 SWR Data 2.0 SWR 1.8 1.6 1.4 Spec 1.2 1.0 5 10 15 Frequency (GHz) 20 25 Figure 4-8.
2.0 SWR 1.8 1.6 Spec 1.4 1.2 1.0 1 2 3 Frequency (GHz) 4 5 Figure 4-9. Model 51101 SWR Data 2.0 SWR 1.8 Spec 1.6 1.4 1.2 1.0 5 10 15 Frequency (GHz) 20 25 Figure 4-10.
5 Pulsed RF Power 5-1 Pulsed RF Power Operation Although this manual discusses power sensors used with average responding power meters, for rectangular pulsed RF signals, pulse power can be calculated from average power if the duty cycle of the reoccurring pulse is known. The duty cycle can be found by dividing the pulse width (T) by the period of the repetition frequency or by multiplying the pulse width times the repetition frequency as shown in Figure 5-1.
5-2 Pulsed RF Operation Thermocouple Sensors Figure 5-2 shows the regions of valid duty cycle and pulse power that apply to the Thermal Sensors. As the duty cycle decreases, the average power decreases for a given pulse power and the noise becomes a limitation. Also, there is a pulse power overload limitation. No matter how short the duty cycle is, this overload limitation applies.
5-3 Pulsed RF Operation Diode Sensors Figure 5-3 shows the valid operating region for the Diode Sensors. As with Thermal Sensors, the bottom end measurement is limited by noise, getting worse as the duty cycle decreases. At the top end, the limitation is on pulse power because even a very short pulse will charge up the detecting capacitors. The burnout level for Diode Sensors is the same for the pulsed and CW waveforms. The minimum pulse repetition frequency is 10 kHz. 0 Pulse Power (dBm) -10 <0.
6 Calculating Measurement Uncertainty 6-1 Introduction This Section has been extracted from the 4530 manual since it provides examples using CW and Peak Power sensors. As such, in calculating Power Measurement Uncertainty , specifications for the 4530 are used. If one of Boonton's other Power Meters are in use, refer to its Instruction Manual for Instrument Uncertainty and Calibrator Uncertainty.
6-2 Uncertainty Contributions The total measurement uncertainty is calculated by combining the following terms: 1. Instrument Uncertainty 2. Calibrator Level Uncertainty 3. Calibrator Mismatch Uncertainty 4. Source Mismatch Uncertainty 5. Sensor Shaping Error 6. Sensor Temperature Coefficient 7. Sensor Noise 8. Sensor Zero Drift 9. Sensor Calibration Factor Uncertainty The formula for worst-case measurement uncertainty is: UWorstCase = U1 + U2 + U3 + U4 + ...
Calibrator Level Uncertainty. This term is the uncertainty in the calibrator’s output level for a given setting for calibrators that are maintained in calibrated condition. The figure is a calibrator specification which depends upon the output level: 50MHz Calibrator Level Uncertainty: At 0 dBm: ± 0.055 dB (1.27%) +20 to -39 dBm: ± 0.075 dB (1.74%) -40 to -60 dBm: ± 0.105 dB (2.45%) 1GHz Calibrator Level Uncertainty: ± (0.065 dB (1.51%) at 0 dBm + 0.03 dB (0.
The sensor reflection coefficient, DSNSR is frequency dependent, and can be referenced in Section 2 of this manual. For most measurements, this is the single largest error term, and care should be used to ensure the best possible match between source and sensor. Figure 6-1. plots Mismatch Uncertainty based on known values of both source and sensor SWR. Sensor Shaping Error.
p= Mismatch Uncertainty Relative Power Uncertainty P.U. = (1 +/- p p ) L S SWR -1 SWR +1 Where p = Load SWR L p = Source SWR S t r a h C Figure 6-1.
use. Sensor temperature drift uncertainty may be assumed to be zero for sensors operating exactly at the calibration temperature. Sensor Noise. The noise contribution to pulse measurements depends on the number of samples averaged to produce the power reading, which is set by the "averaging" menu setting. For continuous measurements with CW sensors, or peak sensors in modulated mode, it depends on the integration time of the measurement, which is set by the "filter" menu setting.
If the measurement frequency is identical to the AutoCal frequency, a calfactor uncertainty of zero should be used, since any absolute error in the calfactor cancels out during AutoCal. At frequencies that are close to the AutoCal frequency, the calfactor uncertainty is only partially cancelled out during AutoCal, so it is generally acceptable to take the uncertainty for the next closest frequency, and scale it down.
Step 3: The Calibrator Mismatch Uncertainty is calculated using the formula in the previous section, using the internal 50MHz calibrator's published figure for DCAL and calculating the value DSNSR from the SWR specification on the 51075's datasheet. DCAL DSNSR = 0.024 (internal calibrator's reflection coefficient at 50MHz) = (1.15 - 1) / (1.15 + 1) = 0.070 (calculated reflection coefficient of 51075, max SWR = 1.15 at 50MHz) UCalMismatch = ± 2 * DCAL * DSNSR * 100 % = ± 2 * 0.024 * 0.070 * 100 % = ± 0.
Step 8: The Sensor Zero Drift calculation is very similar to the noise calculation. For sensor zero drift, the datasheet specification for the 51075 sensor is 100pW, so we'll take the liberty of cutting this in half to 50pW, since we just performed an AutoCal, and it's likely that the sensor hasn't drifted much. UZeroDrift = ± Sensor Zero Drift (in watts) / Signal Power (in watts) = ± 50.0e-12 / 3.16e-9 * 100 % = ± 1.
From the previous example, it can be seen that the two largest contributions to the combined standard uncertainty are the source mismatch, and the sensor calfactor. Typical Example #2: Model 57518 Peak Power Sensor Measurement conditions: Source Frequency: Source Power: Source SWR : AutoCal Source: AutoCal Temperature: Current Temperature: 900 MHz 13 dBm (20mW) 1.12 (reflection coefficient = 0.
Step 4: The Source Mismatch Uncertainty is calculated using the formula in the previous section, using the DUT’s specification for DSRCE and calculating the value DSNSR from the SWR specification found in Section 2. DSRCE = 0.057 (source reflection coefficient at 900 MHz) DSNSR = (1.15 - 1) / (1.15 + 1) ) = 0.070 (calculated reflection coefficient of 57518, max SWR = 1.15 at 0.9 GHz) USourceMismatch = ± 2 * DSRCE * DSNSR * 100 % = ± 2 * 0.057 * 0.070 * 100 % = ± 0.
Step 9: The Sensor Calfactor Uncertainty needs to be interpolated from the uncertainty values given in Table 3-2 (Peak Power Sensor Calibration Factor Uncertainty). At 1 GHz, the sensor’s calfactor uncertainty is 1.7 %, and at 0.5 GHz it is 1.6 %. Note, however, that we are performing our AutoCal at a frequency of 1 GHz, which is very close to the measurement frequency. This means that the calfactor uncertainty cancels to zero at 1 GHz. We’ll use linear interpolation between 0.
7 Warranty Boonton Electronics (Boonton) warrants its products to the original Purchaser to be free from defects in material and workmanship for a period of one year from date of shipment for instrument, and for one year from date of shipment for probes, power sensors and accessories. Boonton further warrants that its instruments will perform within all current specifications under normal use and service for one year from date of shipment.
