M = 16; Fd = 1; Fs = 10; 
Pd = 100; 
msg_d = randint(Pd,1,M); % 生成隨機信號
msg_a = modmap(msg_d,Fd,Fd,'qask',M);%采用QASK調(diào)制方式.
delay = 3; % 提升余弦濾波器的延時
rcv = rcosflt(msg_a,Fd,Fs,'fir/normal',.5,delay);
propdelay = delay .* Fs/Fd + 1; % 繁殖延時
rcv1 = rcv(propdelay:end-(propdelay-1),:); 
N = Fs/Fd;

offset1 = 0;% 無偏移
h1 =  eyediagram(rcv1,N,1/Fd,offset1);
set(h1,'Name','Eye Diagram Displayed with No Offset');

offset2 = 2;% 偏移值為2
h2 = eyediagram(rcv1,N,1/Fd,offset2,'r-');
set(h2,'Name','Eye Diagram Displayed with Offset of Two');