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From: "Robert Orzechowski" <orzechowskirobert@yahoo.com>
Newsgroups: comp.soft-sys.matlab
Subject: ofdm question
Date: Mon, 23 Nov 2009 22:10:21 +0000 (UTC)
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Hello,

I tried to implement very simple OFDM channel. However i met an issue, i cannot solve myself. Could you please help me ?
This is the code:

data=randint(1,k,n);
modulated = pskmod(data);
OFDMmodulated=ifft(modulated);
receivedmodulated = fft(OFDMmodulated);
out = (receivedmodulated ~= modulated);


Why do I got every time receivedmodulated different from modulated, if k is greater than 8 ? I think this is something with fft/ifft usage.

thank you for your help
Robert