Radio Design, Final Project 2005

Due: TBD (12:00 Tues May 10) in class.
We will use the final class time to resolve any last-minute problems.
This project is to be done in groups of 2 or 3, or independently, without collaboration between groups. If you wish to be assigned to a group, let me know at the beginning of the first class when the project is assigned.

Project Description

Design a full duplex (FDD, Freq. Division Duplex) IS-95 CDMA (see cell phone standards at RF cafe or at Phillips Semiconductors ) radio system in the PCS 1900 band with the folowing specifications. Where a specification cannot be met, provide justification. Design objectives: 1) low cost, 2) meet specs, 3) low power, 4) small size. Where a price is not given on a vendor web-page, assume $5 each (use the lowest prices, i.e., the prices for largest quantity -- note all minicircuits parts have prices).

  1. Frequency band:
    Transmit: 1850-1910 MHz, Receive: 1930-1990 MHz
    Set the LO's for 1880 transmit, 1960 receive

  2. Channel Bandwidth: 1.25 MHz
    Adjacent channel rejection (at Fc +/- 1.25 MHz): 60 dB

  3. Receiver noise figure: 10 dB

  4. Receiver sensitivity: TBD dBm at 10 dB S/N

  5. Receiver gain control: 30 dB

  6. Receiver output level: 1 V RMS at minimum input signal power (i.e., at receiver sensitivity). This output is at the final IF frequency. A demodulator is NOT required.

  7. Transmitter power: +24 dBm 1 dB compression

  8. Transmitter/receiver isolation (at first receiver amplifier input at TX frequency): 60 dB

  9. Transmitter output noise floor (at at receive frequency): 10 dB below receiver input noise floor

  10. receiver LO radiation: -80 dBm

  11. Receiver front end spur free dyn range: 70 dB

  12. Transmitter power control: 30 dB

  13. The transmitter and receiver share a single antenna through duplexer

  14. Transmitter/receiver physical size: TBD, X by Y centimeters

  15. Cost: $25

Project Limitations

  1. High frequency filters:
    Use ONLY: Murata filters and duplexers or TOKO duplexers and filters see also: toko filter page

  2. Final IF filters :
    Use ONLY: Sawtek SAW filters with appropriate bandwidth Tiquint/Sawtek SAW

    Note: for filters, if the compression and OIP3 are not stated then set P1dB=max power for the filter, and OIP3 12 dB above max power

  3. Transmit power amplifier:
    Use ONLY: RF microdevices RF 2146 RF micro

  4. Transmit modulator:
    Use ONLY: RF microdevices RF 2422 RF micro
    This is a direct modulation system; you may assume that the modulation signals on I and Q are the full 2.0 volts peak-peak as specified on the spec sheet.

  5. Mixers:
    Use ONLY: Minicircuits level 7 surface mount mixers Minicircuits mixers. Make sure that the RF, IF, and LO frequency ranges are correct in whatever model you choose.

  6. Amplifiers (except as above):
    Use ONLY: Minicircuits surface mount amplifiers Minicircuits amplifiers

  7. Oscillators :
    Use ONLY: Minicircuits surface mount oscillators Minicircuits oscillators
    You may use voltage-controlled oscillators, and assume a suitable external synthesizer loop sets the frequency.

  8. Variable attenuator for power/gain control:
    Use ONLY: M/A-COM part number AT-110 M/A-COM attenuators or try here: M/A-COM

Project Final Report

  1. All reports must be submitted in BOTH MSword and pdf format electronically,


  2. Maximum length: 15 pages single-spaced as outlined below
  3. Format:
    1. Page 1: Cover Page
    2. Page 2: Abstract (1/2 page) Introduction (1/2 page)
    3. Page 3: System block diagram description:
      Describe the transmitter and receiver block diagrams, make sure to describe what each block is, and IF frequencies, etc.
    4. System block diagram 2 pages:
      Page 4: transmitter block diagram
      Page 5: receiver block diagram
    5. Page 6: Cascade analysis description:
      1/2 page: describe the receiver cascade spreadsheet
      1/2 page: describe the transmitter cascade spreadsheet
    6. Cascade analysis spreadsheets:
      Spreadsheet formats per Excell spreadsheet for cascade analysis: download spreadsheet
      you must add rows for power consumption of each stage and total power consumption
      add rows for the cost of each stage and total cost
      Page 7: receiver cascade analysis spreadsheet
      Page 8: transmitter cascade analysis spreadsheet
    7. Page 9: Frequency plan :
      1/3 page: description of frequency plan figures
      1/3 page: transmitter frequency plan figures
      1/3 page: receiver frequency plan figures
    8. Perform a sweep of the receiver as in the Agilent ADS example given in project 3. For this, approximate the Duplexer, RF, and IF filters by elliptic filters that resemble the transfer characteristics of the filters you have chosen (set the stopband to approximate the filters). Turn in the schematic and the frequency response sweep of your receiver. (2 pages: 1 for schematic, 1 for freq response).
      Page 10: ADS receiver schematic
      Page 11: plots of both the passband and image rejection (as 2 separate frequency sweeps as in the ADS example). Make the sweep approximately 5 times as wide as the passband, and sufficient to show selectivity of the radio.
    9. Page 12: Other calculations:
      Make a 3-column table, with the name of each spec in column 1, the formula in column 2, and the answer in column 3. Include
    10. Receiver sensitivity in dBm (see above for dB S/N)
    11. Receiver image rejection (no formula)
    12. Adjacent channel selectivity/rejection
    13. Spur-free dynamic range (without AGC)
    14. LO radiation (no formula)
    15. Transmit power (1dB compression)(no formula)
    16. Transmitter/receiver isolation at TX freq. (no formula)
    17. Transmitter output noise floor at RX freq.
    18. Total cost in dollars(no formula)
    19. Total size in square cm(no formula)
    20. Receiver power consumption in milliwatts (no formula)
    21. Transmitter power consumption in milliwatts (no formula)
    22. battery life (assume 1 amp-hour battery, receiver power only)(no formula)
    23. range in kilometers (assume free-space propagation and 1 watt base station power, 0 dBi transmit and receive antennas, and your calculated receiver sensitivity)
    24. Urban range in kilometers (assume n=3 propagation and 1 watt base station power, 0 dBi transmit and receive antennas, and your calculated receiver sensitivity)

    25. Put the above results in one table !!!
    26. Page 13: Supporting calculations for the table
    27. Page 14: Rough physical layout of transmitter and receiver showing location of all parts at 1:1 scale
    28. Page 15: Parts list icluding vendor, part number, quantity, and cost.
      Hyperlink specs for all parts used !!!
  4. Do not forget to include the LO frequencies on the system block diagrams

Problem resolution. If you have difficulties with your group, follow these guidelines.

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