mod2psk.m

基于MATLAB的2PSK调制,调制解调部分源文件

function modqpsk_output=mod2psk(input)
%m=30; 
%ran(1,1:m)=randn(1,m);                                                         %随机产生qpsk的信号比特1或-1
%input=zeros(1,m);
%for i=1:m
%  if ran(1,i)>0
%      input(1,i)=1;
%   else
%      input(1,i)=-1;
%   end
%end

a=1;       %信号振幅
fc=56000;  %载波频率
Rs=16000;  %码元速率
nn=10;     %每个码元的采样点数nn
fs=nn*Rs;  %采样速率
w=2*pi*fc/fs;
len=length(input);    %码元个数
qsignal=zeros(1,nn*len);
for i=1:len
   qsignal((i-1)*nn+nn/2+1)=input(1,i);
end
prt=ascends(Rs,fs,1/4);     
qwave=zeros(len,nn*len);
prtii=zeros(len,nn*len+36);
prti=zeros(len,nn*len);
for i=1:len
   if i<5
      prtii(i,1:46+(i-1)*nn)=prt(1,36-((i-1)*nn):81);
   else
      prtii(i,5+nn*(i-5)+1:5+nn*(i-5)+81)=prt(1,:);
   end
   prti(i,:)=prtii(i,1:nn*len);
   qwave(i,:)=input(1,i)*prti(i,:);
end
cospart=zeros(1,nn*len);
for i=1:len
   cospart=cospart+qwave(i,:);
end
out=zeros(1,len);
%out=qsig+j*isig;
out=cospart;  %+j*sinpart;
%cosconv=conv(qsignal,prt);
%sinconv=conv(isignal,prt);
%cospart=cosconv(4*fs/Rs+1:4*fs/Rs+n*len);
%sinpart=sinconv(4*fs/Rs+1:4*fs/Rs+n*len);
outsinpart=zeros(1,nn*len);
outcospart=zeros(1,nn*len);
modqpsk_output=zeros(1,nn*len);
for i=1:nn*len;
outsinpart(1,i)=out(1,i)*sin(w*i);
outcospart(1,i)=out(1,i)*cos(w*i);
modqpsk_output(1,i)=outcospart(1,i)+outsinpart(1,i);  %输出
end