qpsk_system_ber_simulation.asv

QPSK误码率计算 AWGN信道下 RAY信道下

% QPSK System Simulation, Pe evaluation
clear;
echo on
SNRindB1=0:1:8;
SNRindB2=0:0.1:8;
% rayleigh channel 
for i=1:length(SNRindB1),
    [pb,ps]=raychn(SNRindB1(i));               % simulated bit and symbol error rates
    smld_bit_ray_err_prb(i)=pb;
    smld_symbol_ray_err_prb(i)=ps;
    disp([ps,pb]);
    echo off;
end;

% awgn channel 
echo on;
for i=1:length(SNRindB1),
    [pb1,ps1]=awgnchn(SNRindB1(i));             
    smld_bit_awgn_err_prb(i)=pb1;
    smld_symbol_awgn_err_prb(i)=ps1;
    disp([ps1,pb1]);
    echo off;
end;
% theory curve
echo on;
for i=1:length(SNRindB2),
    SNR=exp(SNRindB2(i)*log(10)/10);                 % signal to noise ratio
    theo_err_awgn_prb(i)=0.5*erfc(sqrt(SNR));        % AWGN theoretical bit error rate
    theo_err_ray_prb(i)=0.5*(1-1/sqrt(1+1/SNR));     % Rayleigh theoretical bit error rate
    echo off;
end;
echo on;
% Plotting commands follow
semilogy(SNRindB2,theo_err_awgn_prb,'r'),title('BER curves');hold on;
semilogy(SNRindB1,smld_bit_awgn_err_prb,'r*');hold on;
semilogy(SNRindB1,smld_symbol_awgn_err_prb,'ro');hold on;
semilogy(SNRindB2,theo_err_ray_prb,'b');hold on;
semilogy(SNRindB2,smld_bit_ray_err_prb,'b*');hold on;
semilogy(SNRindB2,smld_symbol_ray_err_prb,'bo');
xlabel('Eb/No');ylabel('BER');
legend('theory AWGN curve','simulated AWGN  bit err','simulated AWGN symbol err','theory Rayleigh curve','simulated Rayleigh bit err','simulated Rayleigh symbol err');
echo off;

% Plotting commands follow
%semilogy(SNRindB1,smld_bit_err_prb,'*');
%hold
%semilogy(SNRindB1,smld_symbol_err_prb,'o');
%semilogy(SNRindB2,theo_err_prb);
%echo on;
% Plotting commands follow
%semilogy(SNRindB2,theo_err_awgn_prb,'r'),title('BER curves');hold on;
%semilogy(SNRindB1,smld_bit_awgn_err_prb,'r*');hold on;
%semilogy(SNRindB2,theo_err_ray_prb);hold on;
%semilogy(SNRindB1,smld_bit_ray_err_prb,'*');
%xlabel('Eb/No');ylabel('BER');
%legend('theory AWGN curve','simulated AWGN curve','theory Rayleigh curve','simulated Rayleigh curve');
%echo off;