Test Data using Simulink model of 5



Test Data using Simulink model of 5.2 GHz WLAN

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Figure 1. Receiver Baseband Analog Frequency Response

Receiver IQ Digital Baseband: Input Signal –82 dBm

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Receiver IQ Digital Baseband: Input Signal –65 dBm

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Receiver IQ Digital Baseband: Input Signal –30 dBm

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A/D Discrete Step Performance

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Figure 2. Receiver IQ Digital Baseband, Input signal –65dBm

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Figure 3. Receiver IQ Digital Baseband, Two Tone test, Input power= –30dBm

Transmitter Test: Analog Baseband after D/A, OFDM Symbols

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Figure 4. Transmitter RF signal with OFDM symbols

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Figure 5. Transmitter two tones test for linearity

Transmitter IQ Analog Baseband after Filter, WLAN BPSK packets, 64 OFDM symbols

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Appendix: Scripts used to initialize the models and generate inputs

Receiver constants Board 1:

N1=7*10^(-10); % Noise before sampling filter

N2=7*10^(-20); % Noise added after sampling filter

IQIG=0.44; % IQ imbalance gain in dB

IQIP=1; % IQ imbalance phase in deg

IDCO=(10^(-5.7))^1/2; % In phase DC offset

QDCO=0; % Quadrature DC offset

QI=2e-006*10e-10; % Quantizer interval

Vin=(10^(-6.5)/1000)^0.5; % Input voltage

Ts=1/640e6; % Sampling time (continuous time)

IF=2*pi*8.01e6; % Input freq. in rad/sec

NLG1=-55; % Log nonlinearity gain 1

NLG2=-6; % Log nonlinearity gain 2

NLG3=-16; % Log nonlinearity gain 3

NLC2=3/4; % Log nonlinearity factor 1

NLC4=2; % Log nonlinearity factor 2

NLC6=2; % Log nonlinearity factor 3

Transmitter constants Board 1:

Ts=1/(16*40e6);

fs=1/Ts;

upsample=16;

Noise=10^(-3); % Noise power added after non-linearities

GAIN2=-20; % Non linearities gain factor 2

GAIN3=40; % Non linearities gain factor 3

IQIG=0.44; % IQ imbalance gain in dB

IQIP=1; % IQ imbalance phase in deg

IDCO=(10^(-3.3))^1/2; % In phase DC offset

QDCO=(10^(-3.3))^1/2; % Quadrature DC offset

Vin=10^(-1.5); % Input signal amplitude

IF1=2*pi*1.257e6; % Input freq. in rad/sec

IF2=2*pi*(1.257e6-238e3); % Input freq. in rad/sec

sim_time=2*64*150*16*4*Ts;

A/D impairment modeling

clear all;

fs=16e6;

fc=4.5e3;

nsamples=10*fs/fc;

t=(1:nsamples)/fs;

data=sin(2*pi*fc*t);

AD_precision=7; %number of bits in A/D

quantization_levels=-1:2^(-AD_precision):1-2^(-AD_precision);

d_var=0.5*2^(-AD_precision); % in dB

distorsion=d_var*(2*rand(1,2*2^(AD_precision))-1)/2;

non_unif=quantization_levels+distorsion;

for i=1:nsamples

[temp,level]=min(abs(data(i)-non_unif));

data_q(i)=non_unif(level); % Non-uniformly quantized data

end

OFDM signal generation

fs=40e6;

kk=2;

Ts=1/fs;

I=[];

Q=[];

time=[];

temp=0;

sim_time=2*64*150*Ts;

for t=1:sim_time/64/Ts

data=[sign(rand(1,32)-0.5) zeros(1, (kk-1)*64) sign(rand(1,32)-0.5)];

temp=[(t-1)*64*kk+1:t*64*kk]*Ts;

ofdm_data=sqrt(64*kk)*ifft(data,64*kk);

I=[I real(ofdm_data)];

Q=[Q imag(ofdm_data)];

time=[time; temp'];

end

I_data=[time'; I]';

Q_data=[time'; Q]';

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40 OFDM symbols Avg. SNR= 9.6 dB

40 OFDM symbols Avg. SNR= 23.8 dB

40 OFDM symbols Avg. SNR= 24.9 dB

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