MATLAB脉冲成型

Fd=1;  
Fs=8;   
Delay=3;   
R=0.5;   
[yf,tf]=rcosine(Fd,Fs,'fir/sqrt',R,Delay);  
figure(1);
plot(yf); grid;title('根升余弦滤波器时域波形')
x=randint(100,1)*2-1;%原始输入信号为+1，-1码    
xt=zeros(1,800);    
xt(1:8:end)=x; %%插值后信号

y1=filter(yf,tf,xt); %%成型滤波  
y2=filter(yf,tf,y1); %%用与发送端相同的根升余弦匹配滤波
yt=y2((size(yf)+1)/2:8:end);%%匹配滤波后抽取        
figure(2);    
stem(x(1:40)); grid;title('原始信号输出');
figure(3);
plot(y1(1:100));grid;title('成型信号输出');
figure(4);
plot(y2(1:100));grid;title('匹配滤波信号输出');
figure(5);    
stem(yt(1:40)); grid;title('抽取后信号输出') ;