function H=rey(Nt,Nr)%瑞利衰減信道矩陣模型，Nt為放射天線個數，Nr為接收天線個數
H=zeros(Nr,Nt);
R=eye(Nr*Nt);                                               
X=randn(Nr*Nt,1)/sqrt(2)+j*randn(Nr*Nt,1)/sqrt(2);         
H=reshape(R*X,Nr,Nt);