clear all;
close all;
fc=20000; %载波频率
fs=40000; %采样速率
k=2;
code_size=15*round(k*fs/fc); %信息码元长度
t0=5.5; %信号长度
Ns=256; %采样点个数
fd=125; %符号速率
ts=1/fs; %采样周期
M=64 %码元个数
ti=1/fd; %码元间隔
N=ti/ts;
t=[0:ts:t0];
select=menu('调制方式','2ASK','2FSK','2PSK','4ASK','4FSK','4PSK');
switch select
case 1, % 2ASK signal
x=randint(1,M);
m=sin(2*pi*fc*t);
y=ones(1,M*N);
for i=1:M
for j=1:N
y((i-1)*N+j)=x(i)*m(j);
end
end
T=zeros(6,50);
T(1,1:50)=1;
case 2, %2FSK signal
x=randint(1,M);
m1=sin(2*pi*fc*t);
m2=sin(2*pi*2*fc*t);
y=zeros(1,M*N);
for i=1:M
if x(i)==1;
for j=1:N;
y((i-1)*N+j)=x(i)*m1(j);
end
elseif x(i)==0;
for j=1:N;
y((i-1)*N+j)=(1-x(i))*m2(j);
end
end
end
T=zeros(6,50);
T(2,1:50)=1;
case 3, %2PSK signal,
x=randint(1,M);
m1=sin(2*pi*fc*t);
m2=sin(2*pi*fc*t+pi);
y=zeros(1,M*N);
for i=1:M
if x(i)==1;
for j=1:N;
y((i-1)*N+j)=x(i)*m1(j);
end
elseif x(i)==0;
for j=1:N;
y((i-1)*N+j)=(1-x(i))*m2(j);
end
end
