qpsk.m

关于通信基本原理的仿真

%%%%% QPSK 仿真实例 %%%%%%%%%%%%
clear all;
EbN0dB=1:10;%设定信噪比
errLimit=50;
N=100;
for ii=1:length(EbN0dB)
errCount=0;
totalN=0;
N0(ii)=1/(10^(EbN0dB(ii)/10));
while errCount<errLimit
    source=rand(1,N)>0.5;
    trans=qpsk_mod(source);
    receiver=trans+sqrt(N0(ii)/2)*(randn(1,length(trans))+j*randn(1,length(trans)));
    demodata=qpsk_demod(receiver);
    temp=sum(abs(source-demodata));
    errCount=errCount+temp;
    totalN=totalN+N;
end
ber(ii)=errCount/totalN;
end
ber
semilogy(EbN0dB,ber,'-o');