%Generating 2ASK signal
clc
close all;
%use orthogonal modulation generate modulated siganl
%You can see the original signal v in the code.
fc=1e4; %carrier frequency
fs=1e5; %sample frequency
Rs=2e3; %symbol rate of digital signal
T=1/fs; %sample time
L=1000; %length of signal
t=(0:L-1)*T; %time vector
A=1; %%Ampltitude
v=A*cos(2*pi*1000*t); %modulation signal
xs=sin(2*pi*fc*t);
xc=cos(2*pi*fc*t);
%2ASK
% _________ ______
% signal | | | |
%----------| |________| | so L/fs/T_ask is the length of a_n
% <-T_ask->
%<-----------L points --------------->
T_ask=1/Rs;
a_n=round(rand(1,round(L/(T_ask*fs))));
a_ask=repmat(a_n,T_ask*fs,1);
a_ask=a_ask(:)';
%stairs(a_ask) %figure 2ask,unuse plot
I_ask=0;
Q_ask=a_ask;
y_2ask=I_ask.*xc+Q_ask.*xs;
figure(1)
plot(y_2ask)
figure(2)
plotspectral(y_2ask,fs)
