test.m

用正交调制方法实现模拟调制

fs=100000;%被调制信号x的采样频率
ts=1/fs;%采样间隔
fc=30000;%载波信号的载波频率
t=0:1/fs:0.001;
x=sin(2*pi*10000*t)+sin(2*pi*8000*t);%被调信号x
c=sin(2*pi*fc*t);%载波
%-------------------------------AM----------------
display_x(x);
%----------------------------------------------
I=1+0.95*x;
Q=0;
display_I_Q(I,Q);
%------------------------------------------
display_s_pxxs(I,Q);
title('AM调制功率谱');
%------------------DSB------------------------
display_x(x);
%-----------------------------------------
I=x;
Q=0;
display_I_Q(I,Q);
%---------------------------------------------
display_s_pxxs(I,Q);
title('DSB调制功率谱');
%------------------lsb--------------------
display_x(x);
%-----------------------------------------
I=x;
Q=imag(hilbert(x));
display_I_Q(I,Q);
%---------------------------------------
display_s_pxxs(I,Q);
title('LSB调制功率谱');
%------------------usb--------------------
display_x(x);
%------------------------------------------------------
I=x;
Q=-imag(hilbert(x));
display_I_Q(I,Q);
%---------------------------------------------
display_s_pxxs(I,Q);
title('USB调制功率谱');
%-----------------------FM---------------------
display_x(x);
%--------------------------------------------
kf=100000;
jifen_x(1)=0;
for i=1:length(t)-1
    jifen_x(i+1)=jifen_x(i)+x(i)*ts;
end
I=cos(kf*jifen_x);
Q=sin(kf*jifen_x);
display_I_Q(I,Q);
%---------------------------------------------
display_s_pxxs(I,Q);
title('FM调制功率谱');
%-------------------------AM-FM------------------
display_x(x);
%-------------------------------------------------
I=1+0.95*x;
Q=0;
s=zhengjiao(I,Q);
kf=100000;
jifen_s(1)=0;
for i=1:length(t)-1
    jifen_s(i+1)=jifen_s(i)+s(i)*ts;
end
I=cos(kf*jifen_s);
Q=sin(kf*jifen_s);
display_I_Q(I,Q);
%------------------------------------------
display_s_pxxs(I,Q);
title('AM-FM调制功率谱');