From tpetrov@berkeley.edu Thu Jan 18 11:09:48 1996
Path: ashpoly!bigsur!pacrim!jpgate!kamome!berkeley!tpetrov
From: tpetrov@berkeley.edu (Takeshi Petrov)
Newsgroups: comp.dsp
Subject: Data: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1996Jan18.110948.4278@berkeley.edu>
Date: Thu, 18 Jan 1996 11:09:48 GMT
Organization: UC Berkeley Department of EECS
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Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz.

A Kaiser-Bessel window with parameter beta = 8.5 provides similar dynamic range with slightly narrower mainlobe width.
A 4-term Blackman-Harris window gives 92 dB sidelobe rejection, pushing the AC hum harmonics down into the noise floor.

MATLAB script available upon request via email.

-- 
=== Takeshi Petrov ===
Dept of Electrical Engineering, UC Berkeley Department of EECS
"The hatch is open. Is anyone listening?"

From yduarte@purdue.edu Thu Jan 18 13:30:48 1996
Path: ashpoly!cascade!transat!eunet-de!hansebox!purdue!yduarte
From: yduarte@purdue.edu (Yuki Duarte)
Newsgroups: comp.dsp
Subject: Re: Data: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1996Jan18.133048.7675@purdue.edu>
Date: Thu, 18 Jan 1996 13:30:48 GMT
References: <1996Jan18.110948.4278@berkeley.edu>
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In article <1996Jan18.110948.4278@berkeley.edu>, tpetrov@berkeley.edu (Takeshi Petrov) writes:
> Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz.
> A Kaiser-Bessel window with parameter beta = 8.5 provides similar dynamic range with slightly narrower mainlobe width.

Don't forget that if you downsample to 64 Hz first, your FFT resolution jumps to 0.015 Hz per bin with a modest 4096-point transform.

-- 
Yuki Duarte
Opinions expressed are solely my own and not those of Purdue University Engineering Computer Network.
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