xc_psk.m

高斯加性白噪声下采用MPSK调制的系统BER性能分析

function [y1,y2,pp,dela1]=xc_psk(Fl,Fs,I,Q,x1,x2,M)

M1=length(x1);
N=Fs/Fl;

z=ones(1,N);
X1=x1'*z;
X2=x2'*z;
[r,c]=size(I);
X1=X1.';
X2=X2.';
X1=reshape(X1,1,M1*N);
X2=reshape(X2,1,M1*N);

t=0:1/Fs:(r*c-1)/Fs;

% signal with phase offset
r1=I+j*Q;
%

N1=8;
s0=X1(1:M1*N)+j*X2(1:M1*N);
Y(1:M1)=x1(1:M1)+j*x2(1:M1);      
p=(-0.5:1/N1:0.5-1/N1);
for i=1:N1
           
   h1=0.5+0.5*cos(2*pi*Fl*(t-0.5/Fl+p(i)/Fl));
   s1=s0.*h1(1:M1*N);
   a=r1(1:M1*N);
   zz(i)=abs(sum(a.*conj(s1)))^2;     
   
end
  
   [l]=find(zz==max(zz));
   pp=p(l);
   zz1=sum(r1(1:M1*N).*conj(s1(1:M1*N)));
   zz2=sum(r1(1:M1*N).*conj(r1(1:M1*N)));
   z=(zz1/zz2)/abs(zz1/zz2);
   dela1=angle(z)*180/pi;
   
   
   %r2=r1;
   r2=r1*conj(z);


   h1=0.5+0.5*cos(2*pi*Fl*(t-0.5/Fl+pp/Fl));
	map=[0:M-1].*2*pi/M;  
	map1=cos(map);
   map2=sin(map);
   
for k=M1+1:length(r1)/N
   
   for i=1:M
      s2=s0(N+1:M1*N).*h1((k-M1)*N+1:(k-1)*N);
      sr=[real(s2),map1(i)*h1((k-1)*N+1:k*N)];
      si=[imag(s2),map2(i)*h1((k-1)*N+1:k*N)];
      s1=sr+j*si;
      zf(i)=abs(sum(r2((k-M1)*N+1:k*N).*conj(s1)))^2;
   end
   m=find(zf==max(zf));
   Y(k)=map1(m)+j*map2(m);
   s0=s0(N+1:M1*N);
   s0=[real(s0),map1(m)*ones(1,N)]+j*[imag(s0),map2(m)*ones(1,N)];
   %a1=[real(s0),map1(m)*ones(1,N)];
   %b1=[imag(s0),map2(m)*ones(1,N)];
   %s0=a1+j*b1;
end   

y1=real(Y);
y2=imag(Y);