gusucode.com > 基于4PAM调制性能误码率仿真源码程序 > 基于4PAM调制性能误码率仿真源码程序/BERof4PAM.m
%BER of 4PAM clear all;clc; Nb=10000; %the number of data bits EbN0dB=1:30; %Eb/N0 in dB EbN0 = 10.^(EbN0dB/10); Nerr=zeros(1,length(EbN0)); % initialize Nerr vector for k=1:length(EbN0) b=rand(1,Nb)>0.5; % 0 or 1 random data b2 = reshape(b,2,[])'; for i = 1:length(b2) x(1,i) = (2*b2(i,1) -1) * (2*(b2(i,2)==0)+1); %4PAM mapping end Eb=1; % bit energy N0=Eb/EbN0(k); % noise PSD (W/Hz) varn=N0/2; % noise variance noise=sqrt(varn)*randn(1,Nb/2); % AWGN ~ N(0,varn) r=x+noise; % received signal %4PAM demapping for i = 1:length(r) d2(1,i) = r(1,i)>0; d2(2,i) = abs(r(1,i)) < 2; end d = reshape(d2,1,[]); Nerr(k)=sum(b~=d); % the number of error bits end ber=Nerr/Nb; % bit error rate by simulation EbN0dB2=0:0.01:10; EbN02=10.^(EbN0dB2/10); ber2=Q(sqrt(2*EbN02)); % bit error rate by theory figure; semilogy(EbN0dB,ber,'s'); hold on; semilogy(EbN0dB2,ber2); xlabel('E_b/N_0'); ylabel('BER'); grid on; legend('Simulation', 'Theory');