From dkarlsson@ox.ac.uk Wed Jun 26 23:52:15 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!ox!dkarlsson From: dkarlsson@ox.ac.uk (Dave Karlsson) Newsgroups: comp.dsp Subject: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Jun26.235215.7225@ox.ac.uk> Date: Wed, 26 Jun 1996 23:52:15 GMT Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: WinVN 0.99.5 Lines: 11 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. At 14.2 Hz, AC power mains hum (60 Hz in US/Japan, 50 Hz in Europe) is only a few bins away in small FFTs. MATLAB script available upon request via email. -- Dave Karlsson SupraFAXModem 28.8 @ 28,800 bps "Tape doesn't lie at 02:14. Ears do." From kivanov@cam.ac.uk Thu Jun 27 08:52:15 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!cam!kivanov From: kivanov@cam.ac.uk (Katrin Ivanov) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Jun27.085215.1822@cam.ac.uk> Date: Thu, 27 Jun 1996 08:52:15 GMT References: <1996Jun26.235215.7225@ox.ac.uk> Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: Netscape 1.1N Lines: 10 In article <1996Jun26.235215.7225@ox.ac.uk>, dkarlsson@ox.ac.uk (Dave Karlsson) writes: > Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! -- Katrin Ivanov -- University of Cambridge Computer Laboratory "The carrier frequency does not drift by accident."