[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Discuss-gnuradio] Decoding fm files by MATLAB
From: |
Saeed Beyty |
Subject: |
[Discuss-gnuradio] Decoding fm files by MATLAB |
Date: |
Thu, 15 Jan 2004 06:46:40 -0800 (PST) |
Dear GNURadio-ists
Somewhile ago Eric addressed a file which was the
saved samples of FM radio stations
see this:
http://mail.gnu.org/archive/html/discuss-gnuradio/2004-01/msg00008.html
I tried to decode this file and extract the voice
inside, using MATLAB package.
writting the below m.file for MATLAB, there were no
good results.
Any one can help?
1- How should i open the file? in which format i mean
2- How must i read from the file?the precision is
required.
3- Isn't there any trasmormation neeeded before
demodulation!!?
4- When demodulated the signal, with what frequency
should it be played-back?
%% HERE IS THE MATLAB PROGRAM %%
clc
fid=fopen('C:\fm95_5.dat','r','ieee-le');
Fs=20e6; % Sampling Frequency
Fc=5.75e6; % Center Frequency
precision='int16'; % Data Pecision format.
size=1024*20;
StepSize=1/Fs;
FinalTime=0.5;
for i=1:10
[A,count]=fread(fid,size,precision);%Reading from file
A=-A-115; % Transformation
x = demod(A,Fc,Fs,'fm');
figure(1);
subplot(2,1,1)
plot(x)
subplot(2,1,2)
plot(x)
plot(abs(fft(x)))
soundsc(x,22000)
% 22KHz=22000 is selected as the playback rate
drawnow;
end
fclose(fid);
__________________________________
Do you Yahoo!?
Yahoo! Hotjobs: Enter the "Signing Bonus" Sweepstakes
http://hotjobs.sweepstakes.yahoo.com/signingbonus
- [Discuss-gnuradio] Decoding fm files by MATLAB,
Saeed Beyty <=