matlab-(含教程)多径信道误码率matlab仿真,对比理想信道,普通加性高斯白噪声信道以及多径信道

clc; clear; close all; warning off; addpath 'func\' global dt t df N close all N=2^10; %采样点数 L=64; %每码元的采样点数 M=N/L; %码元数 Rb=2; %码速率是2Mb/s , 码速率单位是Mb/s Ts=1/Rb; %码元间隔 dt=Ts/L; %时域采样间隔 , 时间单位是微秒 df=1/(N*dt) %频域采样间隔 ,频率单位为MHz T=N*dt; %截短时间 Bs=N*df/2; %系统带宽 Na=4; %示波器扫描宽度为4个码元 alpha=0.5; db=12; b=0; a=.5; to=.5; phi=0; t=linspace(-T/2,T/2,N); f=linspace(-Bs,Bs,N)+eps; hr1=sin(pi*t/Ts)./(pi*t/Ts); hr2=cos(alpha*pi*t/Ts)./(1-(2*alpha*t/Ts).^2); hr=hr1.*hr2; HR=abs(t2f(hr)); GT=sqrt(HR); GR=GT; C=1-a*exp(-j*(2*pi*f*to*Ts+phi)); H=C.*HR; h=real(f2t(H)); for loop1=1:16 Eb_N0(loop1)=(loop1-1); eb_n0(loop1)=10^(Eb_N0(loop1)/10); Eb=1; n0=Eb/eb_n0(loop1); sita=n0*Bs; n_err1=0; n_err2=0; for loop2=1:600 a=abs(sign(randn(1,M))); imp=zeros(1,N); imp(L/2:L:N)=a/dt; IMP=t2f(imp); n_ch=sqrt(sita)*randn(size(t)); nr=real(f2t(t2f(n_ch).*GR)); sr1=real(f2t(IMP.*HR))+nr; sr2=real(f2t(IMP.*H))+nr; y1=sign(sr1(L*(.5+b):L:N)); y2=sign(sr2(L*(.5+b):L:N)); n_err1=n_err1+length(find(y1~=a)); n_err2=n_err2+length(find(y2~=a)); end Pe2(loop1)=n_err2/(M*loop2); Pe1(loop1)=n_err1/(M*loop2); eb_n0=10.^(Eb_N0/10); figure(1) semilogy(Eb_N0,0.5*erfc(sqrt(eb_n0)),'r'); hold on; semilogy(Eb_N0,Pe1+eps,'k'); hold on; semilogy(Eb_N0,Pe2+eps,'b'); axis([0,13,1e-6,1]); legend('理想曲线','普通加性高斯白噪声信道','多径信道'); title(['取样时间偏差为0']); end xlabel('Eb/N0') ylabel('Pe')