Evaluation Board Documentation TRF1500 Integrated Dual-Band RF Receiver User’s Guide APPLICATION BRIEF: SWRA004A Wireless Communications Business Unit Digital Signal Processing Solutions July 98
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Contents Abstract ......................................................................................................................... 9 Product Support ......................................................................................................... 10 The TI Advantage Extends Beyond RF to Every Other Major Wireless System Block....................................................................................................................... 10 Related Documentation........................
Contents High-Band Cascaded: Power Conversion Gain Reduction ...................................... 41 High-Band Cascaded: Image Rejection................................................................... 42 High-Band Cascaded: Noise Figure ........................................................................ 43 High-Band Cascaded: RF Input Return Loss .......................................................... 44 High-Band: LO Buffer Output Power .........................................................
Figures Figure 1. TRF1500 Dual-Band Receiver Block Diagram ................................................ 14 Figure 2. Cascaded Block Diagram of the Low-Band Receiver Section ......................... 18 Figure 3. Voltage Divider at Low-Band LNA Input .......................................................... 19 Figure 4. Low-Band LNA Input Configuration ................................................................... 20 Figure 5. Low-Band LNA Output Configuration.......................................
TRF1500 Integrated Dual-Band RF Receiver User’s Guide Abstract The dual-band handset market is expanding very rapidly due to the increase in customers requiring roaming capability. The customer also demands that handsets have an increase in features while keeping the size compact. These dual-band handset requirements put pressure on the integrated circuit manufacturer to be innovative while keeping costs low. To meet this demand, Texas Instruments (TI) has developed the TRF1500 receiver.
SWRA004A Product Support The TI Advantage Extends Beyond RF to Every Other Major Wireless System Block S INGL E CHIP ANAL OG B AS E B AND Audio Audio Interface Interface TMS320C54X TMS320C54X Receiver Receiver TRF1xxx TRF1xxx RF RF Interface Interface Synthesizer Synthesizer TRF2xxx TRF2xxx Power PowerAmp Amp TRF7xxx, TRF7xxx, TRF8xxx TRF8xxx TSC6000 ASIC BACKPLANE DSP DSP Core Core Speaker Speaker Microphone Microphone Modulator Modulator TRF3xxx TRF3xxx S/W S/W User User Display Display R F
SWRA004A Related Documentation The following list specifies product names, part numbers, and literature numbers of corresponding TI documentation. ❑ Dual-Band/Dual-Mode PCS Receiver, Literature number SLWS041A World Wide Web Our World Wide Web site at www.ti.com contains the most up to date product information, revisions, and additions. Users registering with TI&ME can build custom information pages and receive new product updates automatically via email.
SWRA004A Introduction The TRF1500 is a dual-band/dual-mode Personal Communications System (PCS) receiver for cellular telephones operating dual mode (analog and digital) in the 800 MHz band and single mode (digital) in the 1900 MHz band. The TRF1500 consists of a low noise amplifier (LNA) and mixer for each band. For image rejection, the low-band receiver relies on an off-chip image rejection filter between the LNA and mixer while the highband receiver uses an image rejection mixer.
SWRA004A Design Considerations The successful integration of a TRF1500 receiver device into a design is dependent upon the performance of the external components and the quality of the board design and layout. External Components Component tolerance and Q specifications (where applicable) should be observed during the selection of any external components.
SWRA004A TRF 1500 Dual-Band Receiver A block diagram of the TRF1500 dual-band receiver front end down converter is shown in Figure 1. Pin names and descriptions are provided in Table 1. The device operates from a single 3.75 volt supply and its operation is controlled by 6 digital CMOS control lines the TRF1500 operates in 18 different states. The control codes and the corresponding active circuits are given in Table 2. Figure 1.
SWRA004A Table 1.
SWRA004A 16 38 STRONG SIGNAL Strong signal indication 39 40 GND VCC ground VCC 41 GND ground 42 43 LNA IN HIGH BAND LNA IN LOW BAND High band LNA input Low band LNA input 44 45 GND LNA OUT LOW BAND ground Low band LNA output 46 47 GND GND ground ground 48 IR ADJUST C Image rejection adjustment TRF1500 Integrated Dual-Band RF Receiver User’s Guide
SWRA004A TRF1500 Control State The TRF1500 operates in 18 different states: The control code and active circuits are given in Table 2. Table 2.
SWRA004A Low Band Cascaded Receiver Section: LNA, External SAW Filter, Mixer, and LO Buffer Amplifier The TRF1500 low-band receiver section, shown in Figure 2, is an integrated front-end down converter designed to operate in the 800 MHz frequency range. The low-band down converter consists of an LNA, mixer, LO buffer amplifier and an off-chip image reject filter. The digital control allows the low-band to operate in three different states to compensate for the environment in which the TRF1500 is operating.
SWRA004A Low-Band LNA In a typical down-conversion receiver, the LNA is usually placed directly after the antenna and a band-select filter. The purpose of the LNA is to amplify the desired signal being received while adding as little undesired noise and distortion as possible. The TRF1500 LNA is a common emitter amplifier, designed to operate on a single 3.75 volt supply. The LNA has two selectable gain states, normal state or strong signal state, which are controlled with the digital CMOS control lines.
SWRA004A Low-Band LNA Input Figure 4 details the low-band LNA input configuration. The LNA input impedance matching network primarily determines the cascaded gain, noise figure, and input return loss performance of the low-band receiver section. A simple high-pass shunt-L (L10) impedance matching network is used for optimum noise figure performance. The trade off for this optimization is a lower input return loss in the pass-band, but with sufficient attenuation in the stop-band.
SWRA004A Figure 5. Low-Band LNA Output Configuration Surface Acoustic Wave (SAW) Filter The SAW filter is used primarily as an image-reject filter (IRF). The image frequency (fIM) is located at the desired channel frequency (fCH) plus two times the IF frequency (fIF); fIM = fCH + (2 x fIF). The image frequency acts as an interferer to the system. During the down-conversion process, the image and the desired channel are both converted to a common IF.
SWRA004A Low-Band Mixer The purpose of the mixer in a down-conversion receiver is to translate incoming signals from one frequency to another. The low-band mixer in the TRF1500 is a three port high-side injected circuit. The mixer takes two known input signals, a radio frequency (RF) signal and a local oscillator (LO) signal and mixes them together to create a sum and difference intermediate frequency (IF). High-side injection means the LO is higher in frequency than the RF by the IF frequency.
SWRA004A Low-Band Mixer LO Input Figure 8 details the low-band mixer LO input configuration. The input power range level for the LO buffer amplifier is flexible enough (-3 dBm to -7 dBm) to drive the mixer without entering compression. The LO signal is injected through an internal LO buffer amplifier and into the mixer. A high pass shunt-L (L14) and series-C (C17) network is used for impedance matching. The inductor also shunts to ground any undesired noise that could be injected to the mixer. Figure 8.
SWRA004A Figure 9. Low-Band IF Output Configuration Low-Band LO Buffer Amplifier Output Figure 10 details the low-band LO buffer amplifier configuration. The low-band LO buffer amplifier can be used in either singleended or differential mode for a phase lock loop (PLL) configuration. The buffer is digitally controlled and requires a operating drive level ranging from -3 to -7 dBm. For evaluation purposes, a 1:1 transformer balun, with an insertion loss of 2.
SWRA004A Figure 10.
SWRA004A Low-Band Cascaded Test Guide This section involves measuring the cascaded performance of the Low Band LNA, Low Band MIXER and Low Band IF Amp. An external SAW filter is utilized to complete the RF receiver section. All tests apply for an IF output terminated into a 1 kΩ differential load. To match the differential IF output to the 50 Ω test equipment a transformer balun is used. All unused ports are terminated into 50 Ω. Table 3.
SWRA004A 2) Set the LO source power (LO Pin) and the desired frequency (see Table 3). Connect the LO source to the EVM LO input port, J12. 3) Set the spectrum analyzer to measure at the IF frequency (see Table 3). 4) Connect the EVM IF output port, J11, to the spectrum analyzer. 5) Measure the IF output power (IF Pout) at the IF frequency with the spectrum analyzer. 6) Calculate the Cascaded Gain as: Gain = (IF Pout - RF Pin) + Transformer Loss. The transformer loss is 1.8dB.
SWRA004A 4) Connect the EVM IF output port, J11, to the spectrum analyzer. 5) Measure the output power at the IF frequency (IF Pout) with the spectrum analyzer. 6) Enable the strong signal. Measure the output power at the IF frequency (SS IF Pout) with the spectrum analyzer. 7) Calculate Power conversion gain reduction as: Power Conversion Gain Reduction = (IF Pout - SS IF Pout).
SWRA004A b) Next, press the Noise Figure and Gain Button. The corrected LED just above the button should be lit. c) Calibration is complete. Enter the desired IF frequency to measure. Next, the external equipment Loss is considered (RF cable, Transmission line, filter and circulator). 6) The losses are entered in the Noise Figure Meter by using special function 34.x. a) Special Function 34.1 turns on the loss compensation factor. b) Special Function 34.2 is used to enter the loss before the DUT.
SWRA004A Low-Band Cascaded: RF Input Return Loss Control state: 011000 The input return loss of the low band receiver is measured at the EVM low band RF input port, J10. The measurement is performed using a network analyzer. Set up the network analyzer as follows to measure the RF input return loss: 1) Set the network analyzer to measure the low band RF frequency (see Table 3). 2) Set the power range to -35 dBm through -20 dBm, and then set the input power to -30 dBm.
SWRA004A LOW BAND: LO Buffer Output Power Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 This section involves measuring the Low Band LO Buffer Output. All unused ports will be terminated into 50 Ω. The LO buffer output power is measured at the EVM low band LO output port J13. A transformer balun is used to convert the differential output to a single ended output. The measurement is performed using a RF source and a spectrum analyzer.
SWRA004A Low-Band Cascaded: Third Order Input Intercept Point (IIP3) Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 21: The third order input intercept point is the level of the RF input power at which the output power levels of the undesired intermodulation products and the desired IF products are equal. The measurement is performed using three RF sources and a spectrum analyzer. 1) Set the first RF source input power (RF Pin) and frequency (F1) (see Table 3).
SWRA004A Low-Band Cascaded: 1dB RF Input Compression Point Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 The 1 dB input compression point is the RF input power at which the gain compresses 1 dB. Gain compression is when an increase in Pin causes no further increase in the output power (Pout). The measurement is performed using two RF sources and a spectrum analyzer. 1) Set the RF source frequency (see Table 3) and the input power (Pin) to -35 dBm.
SWRA004A -24 -23 -22 -21 -20 0.4 1.2 2.2 3.0 3.0 24.4 24.2 24.2 24.0 23.0 ←1dB Compression Point Low-Band Cascaded: 1dB Blocking Point Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 21 The 1dB Blocking Point is a measurement of the power (dBm) of the interfering signal, measured at the EVM IF output port J11. The measurement is performed using three sources and a spectrum analyzer. 1) Set the RF source frequency and input power (see Table 3).
SWRA004A High-Band Cascaded Receiver Section: LNA, Mixer, LO Buffer Amplifier Cascaded High-Band Receiver Section: LNA, Mixer, and LO Amplifier The TRF1500 high-band receiver section, shown in Figure 11, is an integrated front-end down converter designed to operate in the 1900 MHz frequency range. The high-band down converter consists of an LNA, an image-reject mixer, and LO buffer amplifier circuitry. Figure 11 details the cascaded block diagram with the image reject mixer detailed inside the dotted box.
SWRA004A High-Band RF Input Figure 12 details the high-band RF input configuration. The cascaded noise figure and input return loss performance of the high-band receiver section is determined primarily by the input matching network. The input matching network is designed for optimum noise figure performance, while maintaining good input return loss. A low-pass shunt-C (C20) series-L (L20) network is used for the input impedance matching.
SWRA004A Figure 13 details the TRF1500 configured to utilize the low-band LO input and doubler as the high-band LO. The high-band LO signal is injected into the low-band LO input. The buffered signal is then routed through the doubler. The output of the doubler is routed through an external capacitor (C40) and into the singleended high-band LO input. Figure 14 details the TRF1500 configured to utilize the high-band LO.
SWRA004A High-Band IF Output Figure 15 details the high-band mixer IF output configuration. The high-band mixer has a differential IF output with a 1kΩ differential output impedance. For evaluation purposes, a 16:1 transformer balun, with an insertion loss of 1.8 dB, is used to transform the 1kΩ differential output to a single-ended output which is then matched to 50Ω.
SWRA004A High-Band LO Buffer Amplifier Output Figure 16 details the high-band LO buffer amplifier configuration. The high-band LO buffer can be used in either single-ended or differential mode for a phase lock loop (PLL) configuration. The buffer is digitally controlled and requires an operating drive level ranging from -3 to -7dBm. For evaluation purposes, a 1:1 transformer balun, with an insertion loss of 2.7 dB, is used to convert the differential output to a single-ended output.
SWRA004A High-Band Cascaded Test Guide This section involves measuring the cascaded performance of the High Band LNA, High Band Mixer and High Band IF Amp using the Frequency Doubler. All tests apply for an IF output terminated into a 1 kΩ differential load. A transformer balun is used to match the IF output to the 50 Ω test equipment. All unused ports are terminated into 50 Ω. Table 4.
SWRA004A 2) Set the LO source power (LO Pin) and the desired frequency (see Table 4). Connect the LO source to the EVM LO input port, J12. 3) Set the spectrum analyzer to measure at the IF frequency (see Table 4). 4) Connect the EVM IF output port, J21, to the spectrum analyzer. 5) Measure the IF output power (IF Pout) at the IF frequency with the spectrum analyzer. 6) Calculate the Cascaded Gain as: Gain = (IF Pout - RF Pin) + Transformer Loss. The transformer loss is 1.8dB.
SWRA004A High-Band Cascaded: Image Rejection Control state: 111001 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 Image Rejection is a signal that appears at twice the IF distance from the desired RF signal, located on the opposite side of the LO frequency from the desired RF signal. The measurement is performed using two RF sources and a spectrum analyzer. 1) Set the RF source power (RF Pin) and the desired RF frequency (FRF) (see Table 4). Connect the RF source to the EVM RF input port, J20.
SWRA004A High-Band Cascaded: Noise Figure Control state: 111001 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 22 The cascaded Noise Figure (NF) is measured at the EVM Low Band IF output port, J21. The measurement is performed using an HP8970B Noise Figure Meter. The IF output of the mixer is converted from differential to single ended using a transformer balun. The noise figure meter requires a special setup and calibration since the RF source and receive frequencies are different.
SWRA004A a) Special Function 34.1 turns on the loss compensation factor. b) Special Function 34.2 is used to enter the loss before the DUT. c) Special Function 34.3 is used to enter the room temperature in Kelvin (300°K). d) Special Function 34.4 is used to enter the loss after the DUT. e) Special Function 34.0 is used to turn off the loss compensation factor. The noise figure is measured as follows: 7) Connect the noise source directly to the EVM RF input port, J20.
SWRA004A 1) Set the network analyzer to measure the low band RF frequency (see Table 4). 2) Set the power range to -35 dBm through -20 dBm, and then set the input power to -30 dBm. 3) Perform a full one-port calibration on port 1 of the network analyzer. 4) Set the network analyzer to measure S11. 5) Connect the EVM RF input, J20, to port 1 of the network analyzer. 6) Measure the RF input return loss.
SWRA004A High-Band Cascaded: Power Leakage LO In to RF In Control state: 111001 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 23 The LO leakage at the RF port is measured at the low band RF input port J20. Power leakage is a measure of power in dBm that couples to the RF port. The measurement is performed using a RF source and a spectrum analyzer. 1) Set the LO source frequency and input power (see Table 4). Connect the LO source to the EVM LO input port, J12.
SWRA004A 6) Connect the EVM IF output port, J21 to the spectrum analyzer. 7) Measure the Fundamental output power at the IF frequency (FFund).
SWRA004A RF Pin -35 -34 -33 -32 -31 -30 -29 -28 -27 -26 -25 -24 -23 -22 -21 -20 Pout -10 -9 -8 -7 -6 -5 -4 -3 -2 -1.2 -0.4 0.4 1.2 2.2 3.0 3.0 Gain 25 25 25 25 25 25 25 25 25 24.8 24.6 24.4 24.2 24.2 24.0 23.0 ←1dB Compression Point High-Band Cascaded: 2X2 Spur Performance Control state: 111001 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 2X2 Spur Performance is measured at IF output port J21. The measurement is performed using two sources and a spectrum analyzer.
SWRA004A 8) Calculate 2 X 2 spur performance as 2 X 2 spur performance = 1 Pout - 2 Pout. High Band: 3X3 Spur Performance Control state: 111001 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 3X3 Spur Performance is measured at IF output port J21. The measurement is performed using two sources and a spectrum analyzer. 1) Set the RF source frequency (FRF) and input power (see Table 4). Connect the RF source to the EVM RF input port, J20. 2) Set the LO source frequency and input power (see Table 4).
SWRA004A Low-Band and High-Band Transmit Low- and High-Band Transmit Mixer Figure 17 details the block diagram of the transmit mixer. The TRF1500 provides a transmit mixer for down converting the system transmit signal (low-band or high-band) to a common IF for loop-back testing. The LO input for this mixer can be selected from either the low-band LO input or the high-band LO input by means of the digital control.
SWRA004A Figure 18. Low- and High-Band Transmit Mixer RF Input Configuration Low- and High-Band Transmit Mixer IF Output Figure 19 details the transmit mixer IF output configuration. The transmit mixer has a differential IF output with a 1kΩ differential impedance. For evaluation purposes, a 16:1 transformer balun, with an insertion loss of 1.8 dB, is used to transform the 1kΩ differential output to a single-ended output which is then matched to 50Ω.
SWRA004A Low-Band Transmit Mixer Test Guide This section involves measuring the Transmit Mixer performance. All tests apply for an IF output terminated into a 1 kΩ differential load. To match the IF output to the 50 Ω test equipment a transformer balun is used. All unused ports are terminated into 50 Ω. Table 5. Low-Band Transmit Performance Parameters PARAMETERS Min Typ Max UNIT Tx Mixer Input Frequency Range 824 836.5 849 MHz LO Input Frequency Range Tx Mixer IF Frequency 941 953.
SWRA004A 3) Set the spectrum analyzer to measure at the IF frequency (see Table 5). 4) Connect the EVM IF output port, J31, to the spectrum analyzer. 5) Measure the IF output power (IF Pout) at the IF frequency with the spectrum analyzer. 6) Calculate the Cascaded Gain as: Gain = (IF Pout - RF Pin) + Transformer Loss. The transformer loss is 1.8dB.
SWRA004A b) Next, press the Noise Figure and Gain Button. The corrected LED just above the button should be lit. c) Calibration is complete. Enter the desired IF frequency to measure. Next, the external equipment Loss is considered (RF cable, Transmission line, filter and circulator). 6) The losses are entered in the Noise Figure Meter by using special function 34.x. a) Special Function 34.1 turns on the loss compensation factor. b) Special Function 34.2 is used to enter the loss before the DUT.
SWRA004A 1) Set the network analyzer to measure the low band RF frequency (see Table 5). 2) Set the power range to -35 dBm through -20 dBm, and then set the input power to -30 dBm. 3) Perform a full one-port calibration on port 1 of the network analyzer. 4) Set the network analyzer to measure S11. 5) Connect the EVM RF input, J30, to port 1 of the network analyzer. 6) Measure the RF input return loss.
SWRA004A 1) Set the TX source frequency and input power (see Table 5). Connect the TX source to the EVM TX input port, J30. 2) Set the spectrum analyzer to measure at the TX frequency (see Table 5). 3) Connect the LO In Port, J12, to the spectrum analyzer. 4) Measure the TX leakage power.
SWRA004A -31 -30 -29 -28 -27 -26 -25 -24 -12 -11.2 -10.2 -9.2 -8.4. -7.6 -7.8 -6.0 -23 -5.5 19 18.8 18.8 18.8 18.6 18.4 18.2 18.0←1dB Compression Point 17.5 Low-Band Transmit Mixer: Second Order Input Intercept Point (IIP2) Control state: 010100 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 21 Input intercept point is the level of input RF power at which the output power levels of the undesired intermodulation products and IF products are equal.
SWRA004A Low-Band Transmit Mixer: Third Order Input Intercept Point (IIP3) Control state: 010100 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 21 The third order input intercept point is the level of the RF input power at which the output power levels of the undesired intermodulation products and the desired IF products are equal. The measurement is performed using three RF sources and a spectrum analyzer. 1) Set the first RF source input power (RF Pin) and frequency (F1) (see Table 5).
SWRA004A High-Band Transmit Mixer Test Guide This section involves measuring the High Band Transmit Mixer performance. All tests apply for an IF output terminated into a 1 kΩ differential load. To match the IF output to the 50 Ω test equipment a transformer balun is used. All unused ports are terminated into 50 Ω. Testing the performance of the high transmit mixer can be performed two ways. One being the LO Doubler driven, no EVM modification needed.
SWRA004A Low-Band LNA Stand-Alone Test Guide This section involves measuring the Low Band LNA by itself. All unused ports are terminated into 50Ω. Before measuring the low band LNA by itself the EVM board must be modified as follows: Remove C12 and place C53. The EVM board is now modified to use J15 as the output port of the LNA. Table 7. Low-Band LNA Parameters Parameters Min RF Frequency Range 869 Typ 881.5 Max 894 Units MHz RF Input Power Gain -30 15.
SWRA004A The LNA input return loss is measured at the input Port J10. Using the calibration performed above, set the network analyzer to measure S11. Low-Band LNA: Output Return Loss Control state: 011000 The LNA output return loss is measured at the output port J15. Using the calibration performed above, set the network analyzer to measure S22.
SWRA004A 6) To determine the 1 dB compression point, the RF Pin is increased in steps of 1 dBm until the gain compresses by 1 dB. Repeat step 4 and 5 until the gain compresses by 1dB. RF Pin -35 -34 -33 -32 -31 -30 -29 -28 -27 -26 -25 -24 -23 -22 -21 -20 Pout -20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10.4 -9.4 -8.8 -7.8 -7.0 -7.0 Gain 15 15 15 15 15 15 15 15 15 14.8 14.6 14.6 14.2 14.2 14.0 ←1dB Compression Point 13.
SWRA004A c) After entering the ENR for the desired frequency, press the Frequency button on the front panel to exit. 5) To calibrate the NF Meter: a) Connect the Noise Source directly to the NF meter; press the calibration button twice. b) Next, press the Noise Figure and Gain Button. The corrected LED just above the button should be lit. c) Calibration is complete. Next the external equipment loss is considered (RF cable, Transmission line).
SWRA004A The third order input intercept point is the level of the RF input power at which the output power levels of the undesired intermodulation products and the desired products are equal. The measurement is performed using two RF sources and a spectrum analyzer. 1) Set the first RF source input power (RF Pin) and frequency (F1) (see Table 7). 2) Set the second RF source frequency to the first RF frequency plus 60kHz; F2. 3) Using a RF combiner, connect the RF sources to the EVM RF input port, J10.
SWRA004A Low-Band Receiver Mixer Stand-Alone Test Guide This section involves measuring the Low Band Receiver Mixer. All unused ports will be terminated into 50 Ω. Before measuring the low band Mixer separately, the EVM board must be modified as follows: Remove C12 and place C54. The EVM board is now modified to use J15 as the input port of the Receiver Mixer. Table 8.
SWRA004A 5) Measure the IF output power (IF Pout) at the IF frequency with the spectrum analyzer. 6) Calculate the Cascaded Gain as: Gain = (IF Pout - RF Pin) + Transformer Loss. The transformer loss is 1.8dB. Low-Band Receiver Mixer: Input Return Loss Control state: 011000 The input return loss of the low band receiver mixer is measured at the low band RF input port J15. The measurement is performed using a network analyzer.
SWRA004A Low-Band Receiver Mixer: Power Leakage LO In to RF In Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 23 The LO leakage at the RF port is measured at the low band mixer RF input port, J15. Power leakage is a measure of power in dBm that couples to the RF port. The measurement is performed using a RF source and a spectrum analyzer. 1) Set the LO source frequency and input power (see Table 8). Connect the LO source to the EVM LO input port, J12.
SWRA004A a) On the front panel, press the ENR button. b) Check the ENR value by pressing the Enter button or enter the ENR value for each frequency. c) After entering the ENR for the desired frequency, press the Frequency button on the front panel to exit. 5) To calibrate the NF Meter: a) Connect the Noise Source directly to the NF meter; press the calibration button twice. b) Next, press the Noise Figure and Gain Button. The corrected LED just above the button should be lit. c) Calibration is complete.
SWRA004A J12, may be necessary to eliminate the broad band noise during testing. 9) Connect the EVM IF output port, J11, to the noise figure meter input port. a) A bandpass or low pass filter may be necessary on the IF port to eliminate the LO signal interference and get an accurate noise measurement. 10) Measure the Noise Figure.
SWRA004A -23 -22 -21 -20 -19 -18 -17 -16 -15 -14 -13 -12.2 -11.4 -10.4 -9.6 -8.7 -7.8 -6.8 -6.0 -5.5 10 9.8 9.6 9.6 9.4 9.3 9.2 9.2 9.0 ←1dB Compression Point 8.5 Low-Band Receiver Mixer: Third Order Input Intercept Point (IIP3) Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 21 The third order input intercept point is the level of the RF input power at which the output power levels of the undesired intermodulation products and the desired IF products are equal.
SWRA004A Intermodulation Suppression = FFund - Intermodulation product 10) Calculate the Input Third -Order Intercept Point as: Input Third-Order Intercept = ((Intermodulation Suppression/2) + (RF Pin)) TRF1500 Integrated Dual-Band RF Receiver User’s Guide 71
SWRA004A Appendix A: Test Bench Configuration Figure 20. Test Bench Setup: Power Conversion Gain, Power Conversion Gain Reduction, 1dB RF Input Compression Point, Second Order Input Intercept Point (IIP2), 2x2 Spur Performance, 3x3 Spur Performance, Image rejection and LO Buffer Output Power DC POWER SUPPLY RF SIGNAL SOURCE DC POWER METER RF IN IF OUT SPECTRUM ANALYZER LO IN LO SIGNAL SOURCE DUT Figure 21.
SWRA004A Figure 22. Test Bench Setup: Noise Figure DC POWER DC POWER SUPPLY METER NOISE FIGURE METER IF OUT RF IN NOISE SOURCE LO SIGNAL SOURCE LO IN DUT Figure 23.
SWRA004A Figure 24. Test Bench Setup: Power Leakage RF In to LO In Measurements DC POWER SUPPLY RF SIGNAL SOURCE DC POWER METER RF IN IF OUT 50 Ω SPECTRUM ANALYZER LO IN DUT Figure 25.
SWRA004A Figure 26. Test Bench Setup: LNA Third Order Input Intercept Point (IIP3) Measurement DC POWER SUPPLY DC POWER METER RF SIGNAL SOURCE RF IN RF SIGNAL SOURCE SPECTRUM ANALYZER RF OUT DUT Figure 27.
