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From: "ggk giust" <ggkmath@comcast.net>
Newsgroups: comp.soft-sys.matlab
Subject: how to reverse windowing effect?
Date: Mon, 19 May 2008 23:59:02 +0000 (UTC)
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Greetings, 

I'd like to apply the blackman-harris window to my real-
time data array, before taking its FFT and applying a 
frequency-domain filter to it. 

My question is, when I then do the inverse FFT, how do I 
reverse the effect of windowing (in this case using 
blackman-harris 4 term, -92db) so that the resulting real-
time waveform is as accurate as possible?

Is there some equation I can simply apply? I see a lot of 
references to windowing in the literature, but no 
information about how to reverse the effect of windowing 
when going back from the frequency to the time domain. 
Looking for practical advice how to compute this.

Best regards, -GGK