two2four.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 [y,yn]=two2four(x,m);
%
% BBI 2000 进行2电平到4电平的变换
if nargin<2;m=32;end;
if nargin<1;x=[1 0 1 0 1 0 0 1 1 1 0 1 0 0 0 0 1 1];end;
T=[0 1;3 2];n=length(x);ii=1;
for i=1:2:n-1;
    xi=x(i:i+1)+1;yn(ii)=T(xi(1),xi(2));ii=ii+1;
end;
yn=yn-1.5;y=yn;
for i=1:m-1;y=[y;yn];end;y=y(:)';
%-----------------------------------------
if nargout<1;
    subplot(211);plot(pulse(x));v=axis;axis([v(1:2) -.5 1.5]);
    subplot(212);plot(y);v=axis;axis([v(1:2) -2 2]);
end;