PAMS Technical Documentation RAE–2 Series transceiver Chapter 3 –Transceiver BS8 – BS8_RF Block Original 02/99 Copyright 1999 Nokia Mobile Phones. All rights reserved.
PAMS RAE–2 BS8_RF Technical Documentation AMENDMENT RECORD SHEET Amendment Number Date 02/99 Page 3 – 2 Inserted By Comments Original Original 02/99
PAMS Technical Documentation RAE–2 BS8_RF CONTENTS – RF Page No Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–5 Technical summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RF Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Transmitter Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . Output power . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PAMS RAE–2 BS8_RF Technical Documentation UHF PLL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . UHF VCO module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . UHF local signal input in CRFU_1a . . . . . . . . . . . . . . . . . . . RF/BB/DSP Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Interface Signal Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . Data Interface and Timing . . . . . . . . . . . . . . . .
PAMS RAE–2 BS8_RF Technical Documentation Introduction This document defines the RF–module of the RAE–2 GSM–”engine”. This section contains electrical specifications, functional descriptions, block diagrams etc. Technical summary The RF in the RAE–2 GSM is based on the architecture used in DCT 3. The RAE–2 RF Engine (figure below) is a single side design, on the A–side, with all components located under the PDA unit. Shielding comprises three shielding cans with removable lids.
PAMS RAE–2 BS8_RF Technical Documentation Table 1. Main RF characteristics (continued) Item Values Number of RF channels 124 Power class 4 Number of power levels 15 Note 1 : Standard of primary GSM 900 Band, P – GSM 890 – 915 MHz : Mobile transmit, Downlink 935 – 960 MHz : Mobile receive, Uplink Transmitter Characteristics Item Values Type Upconversion, nonlinear, FDMA/TDMA Intermediate frequency ( phase modulated ) 116 MHz LO frequency range 1006 ...
PAMS RAE–2 BS8_RF Technical Documentation Receiver characteristics Item Values Type Linear, FDMA/TDMA IF frequencies 1st 71 MHz, 2nd 13 MHz LO frequencies 1st LO 1006 ... 1031 MHz, 2nd LO 58 MHz Typical 1 dB bandwidth +/– 90 kHz Sensitivity min.
PAMS RAE–2 BS8_RF Technical Documentation DC characteristics Regulators Transceiver has got a multi function power management IC, which contains among other functions, also 7 pcs of 2.8 V regulators. All regulators can be controlled individually with 2.8 V logic directly or through control register. In GSM direct controls are used to get fast switching, because regulators are used to enable RF–functions. Use of the regulators can be seen in the power distribution diagram. CCONT also provides 1.
TXP VXOENA RAE–2 PA PAMS 1.6 A BS8_RF VBATT Technical Documentation BATTERY Power distribution diagram Original 02/99 3.6 V SYNPWR RXPWR C–CONT VR 1 TXPWR VR 2 2.3 mA VR 3 VR 4 VR 6 84 mA 18 mA VCTCXO BUFFER VXO VR 5 VSYN_2 51 mA Page 3 – 9 CRFU, SUMMA VRX 19.5 mA VTX VCOs BUFFERS VSYN_1 VREF V5V 0.1 mA CRFU, SUMMA PLLs VR 7 COBBA ANAL.
PAMS RAE–2 BS8_RF Technical Documentation Functional descriptions RF block diagram The RF block comprises a conventional dual conversion receiver and the transmitter features an up–conversion mixer for the final TX–frequency. The architecture contains three ICs. Most of the functions are horizontally and vertically integrated. UHF functions except power amplifier and VCO are integrated into CRFU_1a, which is a BiCMOS–circuit suitable for LNA– and mixer–function.
PAMS RAE–2 BS8_RF Power amplifier two way switch TQFP–48 ext.ant.conn. antenna SUMMA Technical Documentation Figure 1.
PAMS RAE–2 BS8_RF Technical Documentation Frequency synthesizers Both VCOs are locked with PLLs into stable frequency source, which is a VCTCXO–module ( voltage controlled temperature compensated crystal oscillator ). The VCTCXO is running at 13 MHz. Temperature effect is controlled with AFC ( automatic frequency control ) voltage, the VCTCXO is locked into the frequency of the base station. AFC is generated by baseband with a 11 bit conventional DAC in COBBA. The UHF PLL is located in the SUMMA.
PAMS RAE–2 BS8_RF Technical Documentation freq. reference AFC–controlled VCTCXO R LP f ref f_out / M PHASE DET. Kvco f_out CHG. PUMP VCO Kd M M = A(P+1) + (N–A)P= NP+A VHF PLL is also located into SUMMA. It comprises a 16/17 ( P/P+1 ) dual modulus prescaler, N– and A–dividers, reference divider, phase detector and charge pump for the loop filter. The VHF local signal is generated with a discrete VCO–circuit. The VHF PLL works in the same way as UHF–PLL.
PAMS RAE–2 BS8_RF Technical Documentation ing signals. Selectivity is required in this place, because of needed linearity and adjacent channel interferers will be on too high signal level for the stages following. The next stage in the receiver chain is AGC–amplifier. It is integrated into SUMMA–ASIC. The AGC has got analog gain control. The control voltage for the AGC is generated with DA–converter in COBBA in baseband. AGC–stage provides accurate gain control range ( min. 57 dB ) for the receiver.
PAMS RAE–2 Technical Documentation BS8_RF from the upconverter. Also it attenuates the wideband noise. This bandpass filter is a SAW–filter. The final amplification is carried out by the third IC, the power amplifier which is a MMIC. It features a 50 ohm input, output requires an external matching network. The MMIC comprises three amplifier stages and interstage matchings. Also included is a gain control, which is controlled with a power control loop.
PAMS RAE–2 BS8_RF Technical Documentation DIR.COUPLER PA RF_OUT RF_IN K cp K PA R1 DETECTOR K K = –R1/R2 det ERROR AMPLIFIER R2 R C Figure 2. Power control feedback loop DOMINATING POLE TXC AGC strategy The AGC–amplifier is used to maintain output level of the receiver almost constant. AGC has to be set before each received burst, this is called pre–monitoring.
PAMS RAE–2 Technical Documentation BS8_RF required. Remaining 10 dB is for gain variations in RX–chain ( for calibration ) Below –95 dBm RF–levels, output level of the receiver drops dB by dB. At –95 dBm level output of the receiver gives 50 mVpp. This is the target value for DSP. Below this it drops down to ca. 9 mVpp @ –110 dBm RF– level. This strategy is chosen because we have to roll off the AGC in PLUSSA early enough, that it won’t saturate in selectivity tests.
PAMS RAE–2 BS8_RF Technical Documentation RF block requirements Duplex filter Parameter Center frequency, ftx,frx Transmit section ftx : 902.5 Receive section unit frx : 947.5 MHz BW ( bandwidth ) at passband +/– 12.5 +/– 12.5 MHz Maximum insertion loss at BW 1.6 ( at +25 deg. C ) 1.9 ( at –20...+85 deg. C ) 3.2 ( at +25 deg. C ) 3.7 ( at –20...+85deg. C ) dB Ripple at BW, peak to peak 1.1 1.5 dB Terminating impedance 50 50 ohms Maximum VSWR 2.2 1.
PAMS RAE–2 BS8_RF Technical Documentation Parameter Min. Typ. Max. Output VSWR Unit/Notes 2 Gain reduction 30 35 dB,room temp. Step accuracy –2 +2 dB,over temp.range Noise figure, when PDATA=0 20 dB RX interstage filter Parameter Min. Typ. Passband Max. Unit 935 – 960 MHz Insertion loss 3.3 dB Ripple in passband 1.3 dB Attenuation DC...890 MHz 45 dB Attenuation 890...915 MHz 25 dB Attenuation 980...1030 MHz 25 dB Attenuation 1025...
PAMS RAE–2 BS8_RF Technical Documentation 1st IF–filter Parameter min. Operating temperature range typ. –20 Center frequency , fo max. unit +75 deg.C 71 MHz Maximum ins. loss at 1dBBW 11 dB Group delay ripple at +/–90 kHz BW 1.
PAMS RAE–2 BS8_RF Technical Documentation 2nd IF Filter Parameter min. typ. Center frequency, fo 1 dB bandwidth, 1dBBW ( relative to 13 MHz ) max. unit 13 MHz +/– 90 kHz Insertion loss 6.0 dB Amplitude ripple at 1dBBW 1.0 dB Group delay ripple at 1 dB BW, peak to peak 1.5 us Attenuations, relative to 13 MHz fo +/– 400 kHz fo +/– 600 kHz fo +/– 800 kHz dB 25 35 45 Terminating impedance 313 330 347 ohm NMP part no. 4510009 Buffer in SUMMA for 2nd IF Parameter Min.
PAMS RAE–2 BS8_RF Technical Documentation Transmitter blocks IQ–modulator and TX–AGC in SUMMA Parameter Supply voltage Min. Typ. Max. 2.7 2.8 2.85 V 28 tbd. mA Typical / Nominal Maximum Current consumption Modulator Inputs (I/Q) Minimum Input bias current (balanced) 100 Input common mode voltage 0.8 Input level (balanced) Input frequency range 0 Input resistance (balanced) tbd Unit Unit / Notes nA V 1.
PAMS RAE–2 BS8_RF Technical Documentation Modulator Output Absolute gain accuracy Minimum Typical / Nominal –2 Maximum Unit / Notes +2 dB Any gain step up/down settling time 10 usec Output 3rd Order Intermodulation products, when both wanted signals are at the level of –12 dBm at the output –35 dB 116 MHz LC TX IF–filter Parameter Min. Center frequency Typ. Max. 116 Insertion loss @ 116 MHz Unit MHz 3.
PAMS RAE–2 BS8_RF Technical Documentation Parameter Min. Typ. Max. 8x116 MHz spurious level Unit –55 Input impedance (balanced) dBc 600//2 ohm//pF Output VSWR, ( with matching network and output balun) 2 TX interstage filter Parameter Min. Passband Typ. Max. Unit 890 – 915 MHz Insertion loss 3.8 dB Ripple in passband 1.5 dB Attenuation DC...813 MHz 35 dB Attenuation 925...935 MHz 7 dB Attenuation 935...960 MHz 15 dB Attenuation 1006...
PAMS RAE–2 BS8_RF Technical Documentation Parameter Symbol Isolation Test condition Min Typ Max Unit Vcc=3.5 V, Vpc=0.2 V, Pin=0 dBm –40 dB 1 us Carrier switching time tr, tf Vcc=3.5 V, Pin=0 dBm Vpc is a pulse from 0.2 to 2.2 V. Rise time up to –0.5 dB from the final power. Fall time vice versa. Total efficiency η Pin= 0 dBm , Pout= +34.3 dBm, Vcc=3.5 V, Tamb = + 25 deg. C Control current Ipc Pin= 0...+5 dBm , Pout= +34.8 dBm, Vcc=3.
PAMS RAE–2 BS8_RF Technical Documentation Directional coupler Parameter Min. Frequency range Typ. 890 Insertion loss Coupling factor Max. 915 MHz 0.5 dB 15 Directivity 13 Impedance level of the main line dB 14 50 VSWR on main line Unit/Notes dB ohm 1.6 Impedance level of the coupled line 50 ohm NMP part no. 4551001 Power detector Parameter Supply voltage Min. Typ. Max. 2.7 2.8 2.85 V 2.
PAMS RAE–2 BS8_RF Technical Documentation Parameter TXC and TXP input resistance Min. Typ. kohm 4 pF 0.5 2.2 POP– and POG–output impedance POP and POG –output current driving capability Unit/Notes 50 TXC and TXP input capacitance Output voltage (POP & POG) Max. V 50 ohm +/– 4 mA Switch on resistance (bet– ween INL& POP or POG) tbd. ohm Voltage of POP/POG when inactive (max. 3.5mA sink) 0.1 V Offset of OP1 and OP2 op.amp.
PAMS RAE–2 BS8_RF Technical Documentation Parameter Min. Typ. Max Unit/.Notes Frequency stability vs. temperature ( ref. @+25 , –20....+75 deg. C ) – 5.0 + 5.0 ppm Frequency stablity vs. supply voltage ( 2.8 V +/– 100 mV ) – 0.1 + 0.1 ppm Frequency stability vs. load change ( 2 kohm//10 pF +/– 10 % ) – 0.3 + 0.3 ppm Aging – 1.0 + 1.0 ppm/year Nominal control voltage, Vc 1.15 V Voltage control range 0.0 2.3 V Voltage control characteristics ( see note 1.
PAMS RAE–2 BS8_RF Technical Documentation Table 3. VHF PLL block in SUMMA, specification (continued) Parameter Min. Typ. Phase comparison frequency Max. 1 Charge pump output current 1 current 2 0.5 2.0 Unit/notes MHz mA Sink to source current matching error of the charge pump +/– 5 % Charge pump current error +/– 10 % Charge pump min. output voltage 0.5 Charge pump max. output voltage V * Vcp–0.
PAMS RAE–2 BS8_RF Technical Documentation UHF PLL Table 4. UHF–synthesizer, Parameter Min. Typ. Max. Start up settling time Unit/Notes 3.0 Settling time +/– 25 MHz 500 ms 800 us, ( into +/– 20 Hz from final frequency ) Phase error 3.7 deg./rms Sidebands +/– 200 kHz +/– 400 kHz +/– 600...+/–1400 kHz +/–1.4... +/– 3.0 MHz > +/– 3.0 MHz –40 –60 –66 –76 –86 dBc Table 5. UHF PLL block in SUMMA Parameter Min. Typ. Max. Unit/notes Input frequency range 650 1700 Input signal level (f<1.
PAMS RAE–2 BS8_RF Technical Documentation Parameter Conditions Oscillation frequency Tuning voltage in center frequency Rating Unit/ Notes Vcc = 2.8 V Vc = 0.8 V Vc = 3.7 V < 1006 > 1031 MHz MHz f = 1018.5 MHz 2.25 +/– 0.25 V Tuning voltage sensitivity in operating frequency range on each spot freq. Vcc = 2.8 V f=1006...1031 MHz 14 +/– 2 MHz/V Output power level Vcc=2.7 V f=1006...1031 MHz –6.0 min. dBm Output impedance and VSWR f=1006...
PAMS RAE–2 BS8_RF Technical Documentation RF/BB/DSP Interface The following three sections describe the hardware and timing interface between RF and the BB/DSP section of the RAE–2. Interface Signal Characteristics The interface signals between the BB and the RF section are shown in the next table as a logical interface. On physical board level baseband supplies voltages from CCONT to separate RF sub–blocks.
PAMS RAE–2 BS8_RF Technical Documentation Table 6. AC and DC Characteristics of RF/BB signals (continued) Signal name TXC From - To Function COBBA SUMMA T Transmitter itt power ower control t l 0...200 kHz RXC Receiver gain control COBBA SUMMA 0...200 kHz TXC and AGC signals originate from the same DAC, controlled in COBBA Data Interface and Timing The SUMMA is programmed via the serial bus SENA, SDATA and SCLK. The data of the SDATA is clocked by rising edge of SCLK.
PAMS RAE–2 BS8_RF Technical Documentation MON 20 ms RX MON RX MON RX MON RX 0.5–2 sec. 4.6 ms 6.9 ms VCXOEN 150 us SYNPWR 150 us RXPWR AGC SENA SDATA/ SCLK Figure 3. Synthesizer timing / IDLE, one monitoring/frame, frame can start also from RX–burst RX time slots 0 TX 1 2 3 MON 4 5 RX 6 7 0 SYNPWR RXPWR TXPWR TXP SENA SDATA/ SCLK RX ONLY UHF– PLL N AND A REGISTERS CLOCKED TX MON RX 50 us max. 50 us max. 50 us max. Figure 4.
PAMS RAE–2 BS8_RF Technical Documentation Transmit Power Timing 542.8 us Pout 8.3...56.7 us TXC TXP 0...56.7 us 0...58 us TXPWR 150 us 50 us Figure 5.
PAMS RAE–2 BS8_RF Technical Documentation SUMMA and Synthesizer Control Registers The following table shows the programmable registers in SUMMA which are used for programmable counters and mode selection. Table 8. Registers addressing A2 A1 A0 HEX addr. Bits Register 0 0 0 0 18 Control register 0 0 1 1 15 VHF VDIV (VDIV2) 0 1 0 2 12 VHF RDIV (RDIV2) 0 1 1 3 18 UHF VDIV 1 0 0 4 12 UHF RDIV PLL Control Word Format Serial data format is shown below.
PAMS RAE–2 BS8_RF Technical Documentation Bit no BS8 Def. Name Purpose S12 0 NF No Function S13 0 NF No Function S14 1 fast Add current to chargepump S15 0 PD_lin UHF Phase detector mode S16 0 UHFOFF 1=UHF synthesizer power down S17 0 RX_SEL digital RX on S18 1 OA_sel Selects pwrctrl opamp 1 TX_AGC_LATCH TXP driven agc gain latching S19 NOTE: Sign. MSB NDIV2 divides reference frequency by programmable figure of 2–2047. Divide ratio less than 2 is prohibited.
PAMS RAE–2 BS8_RF Technical Documentation List of abbreviations ADC Analog to Digital Converter AFC Automatic Frequency Control AGC Automatic Gain Control AM Amplitude Modulation ASIC Application Specific Integrated Circuit AVG Average BB Baseband BiCMOS Bipolar and Complementary Metal Oxide Semiconductor process BT Bandwidth x symbol time (GMSK filter parameter) BW Bandwidth CCONT DCT3 power management ASIC CLK Clock COBBA DCT3 RF/BB and audio interface ASIC CRFU1A DCT3 dualband
PAMS RAE–2 BS8_RF Technical Documentation IMD Intermodulation Distortion LNA Low Noise Amplifier LO Local Oscillator MAD DCT3 DSP/MCU/system logic ASIC (MCU–ASIC–DSP) MMIC Monolithic Microwave Integrated Circuit MON Monitoring slot MS Mobile Station NF Noise Figure OIP3 3rd order Output Intercept Point PA Power Amplifier PCB Printed Circuit Board PLL Phase Locked Loop PM Phase Modulation RA Rural Area (GSM standard fading profile) RBW Resolution Bandwidth RF Radio Frequency
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