Radio Frequency Design to Support Software Transceiver for

Wireless Communications

Author: Cazzie WilliamsWestern Michigan University

Whirlpool CorporationAdvisor/Sponsor:

Dr. Frank Severance and Dr. Bradley J. BazuinWestern Michigan University,

Dept. of Electrical and Computer Engineering

27 October, 2001 MSGC 2001 2

Presentation OverviewIntroductionProject Description

Need and ApplicationGoals and Benefits

Detailed DesignReceiverTransmitter

Test Results/ConclusionsAcknowledgmentsQuestions

27 October, 2001 MSGC 2001 3

Software Transceiver Overview

This work focused on the RF to IF Receiver and IF to RF Transmitter

IBM Compatible

RF to IFReceiver

A to DConvert

DigitalDown-

Converter

DigitalSignal

Processor

Digital Up-Converter

D to AConvert

IF to RFTransmit

Comm. Tower

Satellite

27 October, 2001 MSGC 2001 4

Project Description

! The complete project goals were to define, design, develop, and demonstrate a flexible, electrical and software programmable transceiver (FEAST) for wireless communications.

! The receiver path collects, downconverts and filters radio frequency (RF) energy to an intermediate frequency (IF). The IF is digitally sampled, digitally filtered and downconverted, and then processed in a programmable digital signal processor (pDSP). Audio or data outputs may be provided.

! The transmitter path inputs audio or digital data to the pDSP. The pDSP processes the information before it is digitally upconverted and filtered into a digital IF. The digital IF is converted into analog and then filtered and upconverted to the desired RF band for transmission.

27 October, 2001 MSGC 2001 5

Needs and Applications

• Provide critical radio frequency (RF) to intermediate frequency (IF) translation.

• RF in the Instrumentation, Scientific, and Measurement (ISM) band (902-928 MHz)

• ADC/DAC IFs designed for 64 Msamples-per-sec, 16 MHz center frequency, 26 MHz bandwidth. Tested using 50 Msps, 12.5 MHz center frequency and 26 MHz (aliased) BW.

• Provide a useful dynamic range for signals and a low noise figure to

• Define and provide signal gain to load, not saturate, the ADC

• Define a low noise figure architecture to provide high dynamic range and high sensitivity to weak RF signals.

27 October, 2001 MSGC 2001 6

Stages of a Receiver

H P F

IFF ilter

L P F

902M hz to 928M hz

D to

AC

onve

rt

F s/2

H P F

LP F

S yn th esizer

F c = 915M hz

F ixedL ocal

O scilla to r

F c = 140M hzF c = 140M hz

F c = 788M hz

F c =152.5M hz

F c = 12 .5M hz

F c = 12 .5M hz

F c = 152 .5M hz

27 October, 2001 MSGC 2001 7

RF Receiver

LO Input to RFMixer7 dBm

IF Filter

LO

6

LowpassFilter Amp

7 8

IF to BB Converter Antialiasing

InputRF Waveform

Outputto ADC

-3 dBmAttenuatorLO Input to RF Mixer

7 dBm

LO output to RF Mixer10 dBm

Amp

5

IF Filter

43

SignalGenerator

RF to IF Converter

Amp

2

Pre-selector

1

Component List Type Company Make Model or Part Number1 High Pass Filter Mini-Curcuits SHP 4002 Low Noice Amplier (LNA) Mini-Curcuits ZFL 1000HLN3 Mixer Mini-Curcuits ZFM 5X4 IF Filter (BPF) SAWTEK 8549235 Amplier Mini-Curcuits ZFL 5006 Mixer Mini-Curcuits ZFM 37 Low Pass Filter Mini-Curcuits SLP 308 Amplier Mini-Curcuits ZFL 5009 Voltage Oscillator (VCO) Mini-Circuits ZOS 200

10 Signal Generator HP 8656A

Chart of the Components in RF-to-IF Converter

27 October, 2001 MSGC 2001 8

Gain & Noise ComputationChart of the Gain & Noise of our RF to IF converter

Component Assignments 1 2 3 4 5 6 7 8Gain (dB) -1.00 20.00 -5.90 -11.33 19.00 -4.78 -2.00 19.00Gain (linear) 0.79 100.00 0.26 0.07 79.43 0.33 0.63 79.43

Noise (dB) 1.00 2.90 5.90 11.33 3.80 4.78 2.00 3.80Noise (linear) 1.26 1.95 3.89 13.58 2.40 3.01 1.58 2.40

Total Gain (dB) -1.00 19.00 13.10 1.77 20.77 15.99 13.99 32.99Total Gain (linear) 0.79 79.43 20.42 1.50 119.43 39.73 25.07 1991.13

Total Noise Figure (linear) 1.259 2.455 2.491 3.107 4.038 4.054 4.069 4.125Total Noise Figure (db) 1.00 3.90 3.96 4.92 6.06 6.08 6.10 6.15

27 October, 2001 MSGC 2001 9

Receiver Signal Power Levels

Thermal Noise (kT)26 MHz BW (kTB)Receiver NF (dB(kTB)+NF)

Receiver Noise FloorMinimum Detectable Signal(kTB + NF + Detection Threshold)

ADC LSB < Noise FloorSNR Defines Max InputGain Sets Max Input to ADC

-174 dBm/Hz

-99.85 dBm

+10 dBm ADC Max

-27.70 dBm

-95.70 dBm

26 MH

z -74.15 dB

Gain

32.99 dBA

DC

SN

R68 dB

-93.70 dBm

NF 6.15 dB

Noise PowerConsiderations

+5.29 dBm

Signal PowerConsiderations

27 October, 2001 MSGC 2001 10

Transmitter

InputfromDAC

LO Input to RFMixer7 dBm

IF to RF

LO

6

-10 dBmAttentua

7 8

-3 dBmAttenuatorLO Input to RF Mixer

7 dBm

LO output to RF Mixer10 dBm

5

IF Filter

43

SignalGenerator

Filtered Preamp

21

AmpAmp Post-selector

LowpassFilter

9

Amp

Transmiter

IF to BB Converter Baseband Filter

-20 dBmAttentua

Component List Type Company Make Model or Part Number1 Amplifer Mini-Curcuits ZFL 10002 High Pass Filter Mini-Curcuits SHP 4003 Mixer Mini-Curcuits ZFL 5X4 Amplifer Mini-Curcuits ZFL 5005 IF Filter (BPF) SAWTEK 8549236 Mixer Mini-Curcuits ZFM 37 Attenuator Mini-Curcuits SAT 108 Amplifer Mini-Curcuits ZFL 5009 Low Pass Filter Mini-Curcuits SLP 3010 Voltage Oscillator (VCO) Mini-Circuits ZOS 20011 Signal Generator HP 8656A

Chart of Components for the IF-to-RF Converter

27 October, 2001 MSGC 2001 11

Gain & Noise of the IF to RF ConverterChart of the Gain & Noise of our IF to RF converter

Component Assignments 9 8 7 6 5 4 3 2 1 0Gain (dB) -2.00 19.00 -10.00 -4.78 -11.33 19.00 -5.90 -2.00 17.00 -20.00Gain (linear) 0.63 79.43 0.10 0.33 0.07 79.43 0.26 0.63 50.12 0.01

Noise (dB) 2.00 3.80 10.00 4.78 11.33 3.80 5.90 2.00 6.00 20.00Noise (linear) 1.58 2.40 1.00 3.01 13.58 2.40 139.38 139.38 3.98 100.00

Total Gain (dB) -2.00 17.00 7.00 2.22 -9.11 9.89 3.99 1.99 18.99 -1.01Total Gain (linear) 0.794 7.079 2.239 1.291 0.350 3.123 1.583 1.258 8.903 0.890

Total Noise Figure (linear) 1.58 3.80 3.80 4.20 11.75 23.14 37.33 92.54 39.22 40.46Total Noise Figure (db) 2.00 5.80 5.80 6.23 10.70 13.64 15.72 19.66 15.93 16.07

27 October, 2001 MSGC 2001 12

Test Plan

In order to test the validity of the system, it is planned to execute a series of operational tests based on the following capabilities:

• Continuous Wave (CW) Tests

• Amplitude Demodulation (AM)

• Frequency Demodulation (FM)

27 October, 2001 MSGC 2001 13

Continuous Wave TestsTest 1: Input to ADC

L O

6

L ow pa ssF ilter A m p

7 8

IF to B B C on v er ter A n tia lia sin g

In p u tS ign a l

G e ne ra to r@ 140 M H z

O u tp u t0 dB m

-3 d B mA tte nua to rL O In p u t to R F M ix e r

7 d B m

L O o u tp u t to R F M ix er10 d B m

Component Number Gain/Loss (dB) Power (dBm)0

8 19-19

7 ignored6 -5

Power I/P by signal generator -14

Gain/Loss to Power chart to determine I/P power

27 October, 2001 MSGC 2001 14

Continuous Wave TestsMixing (with high-side injection)

Frequency needed from the VCO: (12.5 + 140) – 140 = 152.5

Voltage needed to produce 152.5 MHz (constant fixed voltage)152.5 MHz = 7.7 MHz (V – 1) + 100 MHzV = 7.82 VDC (constant fixed voltage)

Mixing Products152.5 - 140MHz = 12.5 MHz152.5 + 140 MHz = 192.5 MHz

Low Pass FilterOnly 12.5MHz passes to the ADC

27 October, 2001 MSGC 2001 15

Test 1 ResultsSpectral Analysis of 140MHz Demodulated Signal

-90

-80

-70

-60

-50

-40

-30

-20

-10

00 5000000 10000000 15000000 20000000 25000000

Fre que nc y (Hz)

27 October, 2001 MSGC 2001 16

Continuous Wave TestsTest 2 (IF Receiver Test)

IF Filter

LO

6

LowpassFilter Amp

7 8

IF to BB Converter Antialiasing

InputSignal

Generator@ 140 MHz

Output0 dBm

-3 dBmAttenuatorLO Input to RF Mixer

7 dBm

LO output to RF Mixer10 dBm

Amp

5

IF Filter

4

Component Number Gain/Loss (dB) Power (dBm)0

8 19-19

7 ignored6 -5

-145 19

-334 -11.3

Power I/P by signal generator -21.7

Gain/Loss to Power chart to determine I/P power

27 October, 2001 MSGC 2001 17

Continuous Wave TestsMixing (with high-side injection)

Frequency needed from the VCO: (12.5 + 140) – 140 = 152.5

Voltage needed to produce 152.5 MHz (constant fixed voltage)152.5 MHz = 7.7 MHz (V – 1) + 100 MHzV = 7.82 VDC (constant fixed voltage)

Mixing Products152.5 - 140MHz = 12.5 MHz152.5 + 140 MHz = 192.5 MHz

With a Low Pass FilterOnly 12.5MHz pass to the ADC

27 October, 2001 MSGC 2001 18

Test 2 ResultsSpectral Analysis of IF Receiver Test

-120

-100

-80

-60

-40

-20

00 5000000 10000000 15000000 20000000 25000000

Fre que nc y (Hz)

27 October, 2001 MSGC 2001 19

AM Demodulation Test

LO Input to RFMixer7 dBm

IF Filter

LO

6

LowpassFilter Amp

7 8

IF to BB Converter Antialiasing

InputRF Waveform

Outputto ADC

-3 dBmAttenuatorLO Input to RF Mixer

7 dBm

LO output to RF Mixer10 dBm

Amp

5

IF Filter

43

SignalGenerator

RF to IF Converter

Amp

2

Pre-selector

1

Radio tower

27 October, 2001 MSGC 2001 20

FM Demodulation Test

LO Input to RFMixer7 dBm

IF Filter

LO

6

LowpassFilter Amp

7 8

IF to BB Converter Antialiasing

InputRF Waveform

Outputto ADC

-3 dBmAttenuatorLO Input to RF Mixer

7 dBm

LO output to RF Mixer10 dBm

Amp

5

IF Filter

43

SignalGenerator

RF to IF Converter

Amp

2

Pre-selector

1

Radio tower

27 October, 2001 MSGC 2001 21

ISM Band

27 October, 2001 MSGC 2001 22

Project Results:ISM Transmitting & Receiving

LO Input to RFMixer7 dBm

IF Filter

LO

6

Low passFilter Amp

7 8

IF to BB Converter Antialiasing

-3 dBmAttenuatorLO Input to RF Mixer

7 dBm

LO output to RF M ixer10 dBm

Amp

5

IF Filter

43

SignalGenerator

RF to IF Converter

Amp

2

Pre-selector

1

Outputto

ADC

Receiver

LO Input to RFM ixer7 dBm

IF to RF

LO

6

-10 dBmAttentua

7 8

-3 dBmAttenuatorLO Input to RF M ixer

7 dBm

LO output to RF M ixer10 dBm

5

IF Filter

43

SignalGenerator

Filtered Preamp

21

AmpAmp Post-selector

Low passFilter

9

Amp

Transmiter

IF to BB Converter Baseband Filter

-20 dBmAttentua

InputSignal fromDUC to DAC@ 2 MHz

27 October, 2001 MSGC 2001 23

Project Results

Specification

MeetYes (Y)No (N)

Partially (P)

1Real time data collection and storage for post-processing evaluation P

2Snap shot data analysis capabilities performing spectral analysis and signal correlation P

3Digital filtering for both general spectrum, pre-demodulation and post-demodulation filters Y

4Simple demodulation processing of AM, FM-narrowband, FM-wideband, FSK, and ASK P

5Need to use AD6620,AD6622, AD6640 and DSP Receive and Transmit P

6 Y

7 N

8 P

Receive and Transmit signals in the FM, and AM bandwidth ranges

Receive and Transmit signals in the CDMA bandwidth range

Transmitter and receiver need to be software programmable

27 October, 2001 MSGC 2001 24

RF Design Project Results

Specification

MeetYes (Y)No (N)

Partially (P)

1Transmitting and receiving radio signals at the ISM band range of 900MHz to 920MHz Y

2 Receiver must have a Noise Factor (F) of 4 to 7dB Y

3 Receiver must have a Gain (G) of 34dB Y

4Intermediate frequency must have a bandwidth of 20 to 28MHz Y

5 Transmitter must have a Gain (G) of 0dB Y

27 October, 2001 MSGC 2001 25

Acknowledgments

ECE 481/482 Project Team Members: Garett Spalo and Jonathan BarberWMU – Department of Electrical and Computer EngineeringMichigan Space Grant Consortium – Seed and Fellowship GrantsBAE Systems donation of a Spectrum Analyzer and Synthesized Signal GeneratorDr. Bradley J. Bazuin – Advisor/SponsorDr. Frank Severance- MSGC Board MemberDr. John Gesink – Senior Design CoordinatorDr. S. H. Mousavinezhad – Chair of the Department of ECEDr. I. Abdel-Qader – providing support with DSPDavid F. Florida II, CNE – Lab Supervisor

27 October, 2001 MSGC 2001 26

RF Design to Support SoftwareTransceiver for Wireless

Communications