16QAM.rar_16 QAM _16QAM仿真代码_16qam_faceoru_leather9vw

clear all close all L=16000; M=16; m=10; mu=0.004; a=qam(M,L); a=a/mean(abs(a).^2); a_r=real(a); a_i=imag(a); R_r=mean(a_r.^4)/mean(a_r.^2); R_i=mean(a_i.^4)/mean(a_i.^2); Nf=17; Num=100; f=zeros(Nf,L-Nf+1); % Center spike init f(ceil(Nf/2),1)=1; % Define noise & SNR simulation length snrdb=20; snr=10^(snrdb/10); n=sqrt(1/(2*snr))*(randn(L,1)+i*randn(L,1)); h=[-0.005-0.004j 0.009-0.3j -0.0024-0.104j 0.854+0.52j -0.218+0.273j 0.049-0.074j ... -0.16+0.2j]; % Transmit r=filter(h,1,a)+n; % Define error and equalizer output e=zeros(1,L-Nf+1); e_r=zeros(1,L-Nf+1); e_i=zeros(1,L-Nf+1); y=zeros(1,L-Nf+1); y_r=zeros(1,L-Nf+1); y_i=zeros(1,L-Nf+1); isi_ave=zeros(1,L-Num-Num+1); for t=1:m, for k=Nf:L, R=r(k:-1:k-Nf+1); y(k-Nf+1)=R.'*f(:,k-Nf+1); y_r(k-Nf+1)=real(y(k-Nf+1)); y_i(k-Nf+1)=imag(y(k-Nf+1)); e_r(k-Nf+1)=y_r(k-Nf+1)*(y_r(k-Nf+1)^2-R_r); e_i(k-Nf+1)=y_i(k-Nf+1)*(y_i(k-Nf+1)^2-R_i); e(k-Nf+1)=e_r(k-Nf+1)+i*e_i(k-Nf+1); f(:,k-Nf+2)=f(:,k-Nf+1)-mu*e(k-Nf+1)*conj(R); end; for jj=Num:L-Num, cr=conv(h,f(:,jj)); isi(jj-Num+1)=(sum(abs(cr).^2)-max(abs(cr).^2))/max(abs(cr).^2); end; isi_ave=isi_ave+isi; end; isi_ave=isi_ave/m; isi_ave=10*log10(isi_ave); % Run new data to get eye diagram % make sure to get odd samples ynew=filter(f(:,L-Nf+1),1,r); ynew=ynew(Num:length(ynew)-Num); figure(1); plot(real(r),imag(r),'*'); grid, title('输入信号的星座图'); xlabel('Real'), ylabel('Image') figure(2); subplot(2,2,1), plot(real(a),imag(a),'*'); grid,title('原始星座图'); xlabel('Real'),ylabel('Image') % subplot(3,2,2), % plot(real(x),imag(x),'o'); % grid, title('均衡器输入信号的星座图'); xlabel('Real'), ylabel('Image') subplot(2,2,2), plot(real(ynew),imag(ynew),'*'); % show the pattern of the equalized symbols grid, title('均衡后星座图'), xlabel('Real'), ylabel('Image') subplot(2,2,3), plot(isi_ave); % show the convergence grid, title('ISI'), xlabel('迭代次数'), ylabel('ISI（dB）') subplot(2,2,4), plot(real(y),imag(y),'*'); grid, title('均衡器输入信号的星座图'); xlabel('Real'), ylabel('Image')