constel.m

交全面的给出了好几种调制解调方案的matlab代码,又ASK,BPSK,FSK,QAM等的源代码 对通信领域的研究人员很有帮助

function c=constel(x,fs,fb,fc);
%
% Usage:ph=phdet(x,fs,fc);BBI 2000
if nargin<4;fc=2; end;
if nargin<3;fb=1; end;
if nargin<2;fs=32; end;
if nargin<1;
    t=(0:255)/fs;x=cos(2*pi*fc*t+.25*pi);
end;
N=length(x);m=2*fs/fb;n=fs/fc;
i1=m-n;i=1;ph0=(i1-1)*2*pi/n;
while i<=N/m;
    xi=x(i1:i1+n-1);y=2*fft(xi)/n;c(i)=y(2);
    i=i+1;i1=i1+m;
end;
%-------------------------------------------------
if nargout<1;
    cmax=max(abs(c));
    ph=(0:5:360)*pi/180;plot(1.414*cos(ph),1.414*sin(ph),'c');
    hold on;
    for i=1:length(c);
        ph=angle(c(i))-ph0+pi;%+pi/2;
        a=abs(c(i))/cmax*1.414;
        plot(a*cos(ph),a*sin(ph),'r*');
    end;
    plot([-1.5 1.5],[0 0],'k:',[0 0],[-1.5 1.5],'k:');
    hold off;axis equal; axis([-1.5 1.5 -1.5 1.5]);
end;