The Designer's Guide Community Forum

The Designer's Guide Community Forum
https://designers-guide.org/forum/YaBB.pl
Measurements >> Other Measurements >> Problem with dft processing gain
https://designers-guide.org/forum/YaBB.pl?num=1219416174

Message started by shaikh_sarfraz on Aug 22^nd, 2008, 7:42am

Title: Problem with dft processing gain
Post by shaikh_sarfraz on Aug 22^nd, 2008, 7:42am

Hi,
I am using rectangular window for converting a time domain signal to frequency domain.
Now, for finding SNR, do I need to subtract DFT processing gain from the final expression.

I mean, does rectangular windowing cause any DFT processing gain????

Best Regards
Sarfraz

Title: Re: Problem with dft processing gain
Post by shaikh_sarfraz on Aug 26^th, 2008, 11:09pm

Just to give some more information,
I want to find the SNR of an ADC. So I am using coherent sampling with rectangular window .

Is there any DFT processing gain associated with Rectangular Windows (just need confirmation)?

Best Regards
Sarfraz

Title: Re: Problem with dft processing gain
Post by ywguo on Sep 23^rd, 2008, 10:18pm

Hi Sarfraz,

From the definition of DFT, the rectanguar window has a DC gain of N if the window is N samples long in time domain. However, that is not important, because we often normalize the magnitude of the DFT with the DC gain of the window.

Please refer to Appendix A, Schreier and Temes 2005, for the details.

Yawei