mod_mpsk.m

基带数字信号通过成形滤波（选用升余弦滚降函数）然后进行载波调制

function s_mpsk=mod_mpsk(data,sample,M,fb,fc)

%clear;clc;
%M=2;N=20;
%data=randint(1,N,M);
%data=[1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 ];
%sample=16;

Tc=1/fb;

d_am=exp(j*data*2*pi/M);

di=real(d_am);dq=imag(d_am);

pulse_pskI=pulse_mpsk(di,fb,sample);
pulse_pskQ=pulse_mpsk(dq,fb,sample);

fs=fb*sample;ts=1/fs;
%delta_f=500;fc1=fc-delta_f;fc2=fc+delta_f;

t=[0:length(pulse_pskI)-1]*ts;
c=cos(2*pi*fc.*t);
s_pskI=pulse_pskI.*c;
t2=[0:length(pulse_pskQ)-1]*ts;
cc=sin(2*pi*fc.*t2);
s_pskQ=pulse_pskQ.*cc;

s_mpsk=s_pskI+s_pskQ;

%s_mpsk=s_mpsk/max(s_mpsk);
%figure
%plot(s_mpsk)