ex1.m

BPSK,Pi/4DQPSK,16QAM调制解调的实现：实现具体的调制解调功能

clear;
fb=8;
fc=8;
fs=512;
nn=8;
msg=[0 0 1 1 1 0 0 1]; 
msg1=msg*2-1;

t=0:1/fs:511/fs;
for j=1:8
    for i=1:64
        I((j-1)*64+i)=msg1(j);
       
        i=i+1;
    end
    j=j+1;
end
yy=I.*sin(2*pi*fc*t)*(-1);
figure(1)
plot(t,yy);
axis([0 1 -1.2 1.2])
y1=yy.*sin(2*pi*fc*t)*(-1);
figure(2)
plot(t,y1)
[b,a]=butter(2,2*fb/fs);
y2=filtfilt(b,a,y1);
figure(3)
plot(t,y2)
In=sign(y2);
figure(4)
plot(t,In)
axis([0 1 -1.2 1.2])