1. 2.4GHz Single Balanced Mixer Andrew Bacon Jacqueline Griffin John Stone

2. Mixer Specifications IF Frequency: 140 MHz RF Frequency: 2400-2485 MHz RF Power: -10 dBm LO Frequency: 2260-2345 MHz LO Power: 8 dBm Conversion Loss: > -9.5 dB LO-RF Rejection: < -20 dB LO-IF Rejection: <-30 dB

3. Mixer Design

4. Balun Design and Simulation Used an  r of 2.9 for second layer to compensate for it being buried.

5. Diode Model and Simulation

6. Matching Design and Simulation Find input impedance of diodes at 2.4 GHz Design single stub network between diodes and balun Let simulator optimize LC filter at output

7. Mixer Layout LO Return IF Block LO Port RF Port Diode Matching Circuits LC LPF Coupler IF Port Diode Ghetto Lettering 2.6 in 1.7 in

8. Resulting Board (Problems) All holes that were supposed to be connected to ground were not All holes that were not supposed to be connected to ground were Missing parts of Traces

9. Mixer Board Top ViewBottom View

10. Measurement Methodology Down Converter Used spectrum analyzer because it has low error (~.1dB) Low frequency cable was taken out of measurement through calibration High frequency cable was taken out of measurement by measuring the response of the cable after measuring the mixer Used spectrum analyser to measure IF rejection

11. Measurement Diagram (Down Converter) IFRF LO 2.260 000 00 GHz Vector Network Analyzer RFLO LO Signal Generator

12. Downconversion Results RF Freq (GHz) 2.42.442.4852.42.442.485 LO Freq (GHz) 2.262.302.3452.262.302.345 Conv. Loss -10.78-11.48-13.00-8.475-8.588-18.52 LO-IF Isolation (dBm) -59.3-60.5-58.79-71.37-69.31-69.99 MeasurementsSimulation

13. Downconverter Measurements RF Freq = 2.40 GHzRF Freq = 2.44 GHz RF Freq = 2.485 GHz

14. Frequency Shift Measurements Desired Frequency Response Results Adjusting the IF return led to being able to shift the frequency Band up to 2.0 GHz on another board If inductor were used this adjustment would be much easier As stub is shorted to ground at end. RF freq Conversion Loss

15. Simulation Verification RF freq (GHz) Conversion Loss

16. Measurement Methodology Up Converter Used spectrum analyzer

17. Measurement Diagram (Up Converter) 1 400000 00 MHz 2.260 000 00 GHz IFRF LO IF Signal Generator LO Signal Generator

18. Upconversion Spurious Levels Freq Range (GHz) Spurious Spec LO 2.26 GHz LO 2.30 GHz LO 2.345 GHz LO 2.26 GHz LO 2.30 GHz LO 2.345 GHz 2.4- 2.485 <-50 dBc-- 2.485- 2.90 < -40 dBc -33.55 -43.9 -46.54-40.43-41.28 -36.85 -39.58 -41.91 -40.83 -43.53 2.325- 2.40 < -40 dBc -- 1.0- 2.212 <-30 dBc-36.62 -45.89 -35.92 -44.69 -35.89 -35.4 -49.77 -43.87 -44.06 -50.49 -41.35 -76.62 MeasurementsSimulation

19. Upconverter Measurements LO Freq = 2.26 GHzLO Freq = 2.30 GHz LO Freq = 2.345 GHz

20. Upconverter Sweep Measurement LO Frequency Swept from 2.26 GHz to 2.345 GHz

21. LO-RF Isolation

22. Simulations vs. Measurements Possible Reasons for inaccuracies Fabrication (~.5dB) Inaccurate  r Multilayer simulation problems with ADS

23. Improvements Use inductor for IF return (will allow more tuning) Verify technology parameters Verify ADS’s simulation abilities

24. Questions