FSK Demodulation

[engradnan]

Hi,

I am a university student and trying to implement FSK demodulation using MATLAB, please help me. consider me as a beginner . . from where i should start?

[aya2002]

see matlab help

Communications Toolbox
Examples

you will find many examples for this problem

[aya2002]

also see this example (my example)

clc;
clear all;
disp('M-Array PSK Modulation')
%create a random digital message
M=input ('M= '); %alphabet size
x=randint(input('Number of binary bit stream = '),1,M);
nsample=40; %oversampling rate.
%use M-PSK modulation to produce y
y=modulate(modem.pskmod(M),x);
%%
%follow with rectangular pulse shaping.
ypulse=rectpulse(y,nsample);
stem(y(1:10),'filled'),grid;
%%
%%transmit signal through an AWGN Channel
ynoisy=awgn(ypulse,input('SNR in dB = '),'measured');
%%
%Create scattet plot from noisy data
scatterplot(ynoisy),grid;
%%
%Downsample at the reciever.
ydownsample=intdump(ynoisy,nsample);
%%
%Demodulate ynoisy to recover the message.
z=demodulate(modem.pskdemod(M),ydownsample);
figure;
subplot(2,1,1);
stem(x(1:10),'filled'),grid;
subplot(2,1,2);
stem(z(1:10),'filled'),grid;
%%
%Check symbole erroe rate.
[num ty]=symerr(x,z)