tu1-12-2.asv

我自己在学习空时编码一书时编写的第一章的仿真程序

SNR_dB=15;
SNR=10.^(SNR_dB./10);
for n=[1 2 4 8]
    simtimes=80000;
    C_E(simtimes)=0;%init
    for s=1:simtimes
        H=(randn(n,n)+j.*randn(n,n))./sqrt(2);
        C_E(s)=1./n.*log2(det(eye(n,n)+SNR./n.*(H'*H)));
    end
    dx=0.01;
    [c,xout] = hist(C_E, 0:dx:10);
    pdf=c./simtimes./dx; %pdf fun
    %plot(xout,pdf);
    %sum(pdf).*dx %verify pdf fun
    plot(xout, 1-cumsum(pdf).*dx);hold on;
    axis([0 4 0.9 1]);grid on;
end
xlabel('容量n/(bit/s/Hz)');
ylabel('大于横坐标的概率 [容量n>横坐标的概率]');
text(1.7,0.935,'n=1');
text(2.6,0.975,'n=2');
text(3.2,0.985,'n=4');
text(3.6,0.995,'n=8');