%示意雙極性NRZ基帶信號經過帶寬受限信號造成的碼間干擾影響及其眼圖,文件mjgr.m
clear all;
close all;

N =1000;
N_sample=8;     %每碼元抽樣點數
Ts=1;
dt = Ts/N_sample;
t=0:dt:(N*N_sample-1)*dt;

gt = ones(1,N_sample);   %數字基帶波形
d = sign(randn(1,N));    %輸入數字序列
a = sigexpand(d,N_sample); 
st = conv(a,gt);         %數字基帶信號

ht1 = 5*sinc(5*(t-5)/Ts);
rt1 = conv(st,ht1);

ht2 = sinc((t-5)/Ts);
rt2 = conv(st,ht2);

eyediagram(rt1+j*rt2,40,5);    %調用Matlab畫眼圖的函數，行40點，表示5只眼