(完整word版)数字基带信号功率谱的MATLAB仿真程序代码(word文档良心出品).doc

clearall;closeall;Ts=1;N_sample=8;dt=Ts/N_sample;N=1000;t=0:dt:(N*N_sample-1)*dt;T=t(end);gt1=ones(1,N_sample);gt2=ones(1,N_sample/2);gt2=[gt2zeros(1,N_sample/2)];mt3=sinc((t-5)/Ts);gt3=mt3(1:10*N_sample);d=(sign(randn(1,N))+1)/2;data=sigexpand(d,N_sample);st1=conv(data,gt1);st2=conv(data,gt2);d=2*d-1;data=sigexpand(d,N_sample);st3=conv(data,gt3);[f,st1f]=T2F(t,[st1(1:length(t))]);[f,st2f]=T2F(t,[st2(1:length(t))]);[f,st3f]=T2F(t,[st3(1:length(t))]);figure(1)subplot(321)plot(t,[st1(1:length(t))]);grid;axis([020-1.51.5]);ylabel('单极性NRZ波形');subplot(322)plot(f,10*log10(abs(st1f).^2/T));grid;axis([-55-4010]);ylabel('单极性NRZ攻略谱密度');subplot(323)plot(t,[st2(1:length(t))]);grid;axis([020-1.51.5]);ylabel('单极性RZ波形');subplot(324)plot(f,10*log10(abs(st2f).^2/T));axis([-55-4010]);ylabel('单极性RZ功率谱密度（dB/Hz）');subplot(325)plot(t-5,[st3(1:length(t))]);grid;axis([020-22]);ylabel('双极性sinc波形');subplot(326)plot(f,10*log10(abs(st3f).^2/T));grid;axis([-55-4010]);ylabel('sinc波形功率谱密度');xlabel('f*Ts');