MATLAB/Simulink通信仿真的应用demo

%仿真V-BLAST结构MMSE检测算法性能，调制方式为QPSK clear all Nt = 4; %发射天线数 Nr = 4; %接收天线数 N = 10; %每帧的长度 L = 10000; %仿真的总帧数 EbN0 = 0:2:20; M = 4; %QPSK调制 x = randi([0,1],N*L,Nt); %信源数据 s = pskmod(x,M,pi/4); %QPSK调制 for index=1:length(EbN0) x1 = []; x2 = []; x3 = []; for index1 = 1:L h = randn(Nt,Nr)+j*randn(Nt,Nr); %Rayleigh衰落信道 h = h./sqrt(2); %信道系数归一化 sigma1 = sqrt(1/(10.^(EbN0(index)/10))); %每根接收天线的高斯白噪声标准差 n = sigma1*(randn(N,Nr)+j*randn(N,Nr)); %每根接收天线的高斯白噪声 w = h'*inv(h*h'+2*sigma1.^2*diag(ones(1,Nt))); %w的最优解 y = s((index1-1)*N+1:index1*N,:)*h+n; %信号通过信道 yy = y; y1 = y*w; %无干扰消除时的MMSE检测 temp1 = pskdemod(y1,M,pi/4); %无干扰消除时的解调 x1 = [x1;temp1]; %无干扰消除时的解调结果 temp2(:,Nt) = temp1(:,Nt); y = y-pskmod(temp2(:,Nt),4,pi/4)*h(Nt,:); %非理想干扰消除时，接收信号矩阵的更新 temp3(:,Nt) = temp1(:,Nt); yy = yy-s((index1-1)*N+1:index1*N,Nt)*h(Nt,:); %理想干扰消除时，接收信号矩阵的更新 h = h(1:Nt-1,:) for ii=Nt-1:-1:1 w = h'*inv(h*h'++2*sigma1.^2*diag(ones(1,ii))); %信道矩阵更新后的w y1 = y*w; %非理想干扰消除的检测与解调 temp2(:,ii)=pskdemod(y1(:,ii),M,pi/4); y = y-pskmod(temp2(:,ii),4,pi/4)*h(ii,:); yy1 = yy*w; %理想干扰消除的检测与解调 temp3(:,ii)=pskdemod(yy1(:,ii),M,pi/4); yy = yy-s((index1-1)*N+1:index1*N,ii)*h(ii,:); h = h(1:ii-1,:); end x2 = [x2;temp2]; %非理想干扰消除时的结果 x3 = [x3;temp3]; %理想干扰消除时的结果 end [temp,ber1(index)] = biterr(x,x1,log2(M)); %无干扰消除时的系统误码 [temp,ber2(index)] = biterr(x,x2,log2(M)); %非理想干扰消除时的系统误码 [temp,ber3(index)] = biterr(x,x3,log2(M)); %理想干扰消除时的系统误码 [temp,ber24(index)] = biterr(x(:,1),x2(:,1),log2(M)); %非理想干扰消除时第4层的系统误码 [temp,ber23(index)] = biterr(x(:,2),x2(:,2),log2(M)); %非理想干扰消除时第3层的系统误码 [temp,ber22(index)] = biterr(x(:,3),x2(:,3),log2(M)); %非理想干扰消除时第2层的系统误码 [temp,ber21(index)] = biterr(x(:,4),x2(:,4),log2(M)); %非理想干扰消除时第1层的系统误码 [temp,ber34(index)] = biterr(x(:,1),x3(:,1),log2(M)); %理想干扰消除时第4层的系统误码 [temp,ber33(index)] = biterr(x(:,2),x3(:,2),log2(M)); %理想干扰消除时第3层的系统误码 [temp,ber32(index)] = biterr(x(:,3),x3(:,3),log2(M)); %理想干扰消除时第2层的系统误码 [temp,ber31(index)] = biterr(x(:,4),x3(:,4),log2(M)); %理想干扰消除时第1层的系统误码 end semilogy(EbN0,ber1,'-ko',EbN0,ber2,'-ro',EbN0,ber3,'-go') title('V-BLAST结构ZF检测算法性能') legend('无干扰消除','非理想干扰消除', '理想干扰消除') xlabel('信噪比Eb/N0') ylabel('误比特率（BER）') figure semilogy(EbN0,ber34,'-ko',EbN0,ber33,'-ro',EbN0,ber32,'-go',EbN0,ber31,'-bo') title('理想干扰消除ZF检测算法性能') legend('第1层','第2层', '第3层', '第4层') xlabel('信噪比Eb/N0') ylabel('误比特率（BER）') figure semilogy(EbN0,ber24,'-ko',EbN0,ber23,'-ro',EbN0,ber22,'-go',EbN0,ber21,'-bo') title('非理想干扰消除ZF检测算法性能') legend('第1层','第2层', '第3层', '第4层') xlabel('信噪比Eb/N0') ylabel('误比特率（BER）')