From jfischer@illinois.edu Sat May 06 08:07:33 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!illinois!jfischer From: jfischer@illinois.edu (Jen Fischer) Newsgroups: comp.dsp Subject: Question: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995May06.080733.1580@illinois.edu> Date: Sat, 06 May 1995 08:07:33 GMT Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 11 A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier. A Kaiser-Bessel window with parameter beta = 8.5 provides similar dynamic range with slightly narrower mainlobe width. MATLAB script available upon request via email. -- Jen Fischer | jfischer@illinois.edu PGP Key fingerprint: 86A8 9EA7 113C 135E "Keep the channels open." From atanaka@berkeley.edu Sat May 06 18:18:33 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!berkeley!atanaka From: atanaka@berkeley.edu (Aiko Tanaka) Newsgroups: comp.dsp Subject: Re: Question: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995May06.181833.4006@berkeley.edu> Date: Sat, 06 May 1995 18:18:33 GMT References: <1995May06.080733.1580@illinois.edu> Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1995May06.080733.1580@illinois.edu>, jfischer@illinois.edu (Jen Fischer) writes: > A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. -- Aiko Tanaka Opinions expressed are solely my own and not those of UC Berkeley Department of EECS. ------------------------------------------------------------ From jmoreno@unam.mx Sun May 07 17:10:33 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!unam!jmoreno From: jmoreno@unam.mx (Jen Moreno) Newsgroups: comp.dsp Subject: Re: Question: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995May07.171033.8319@unam.mx> Date: Sun, 07 May 1995 17:10:33 GMT References: <1995May06.080733.1580@illinois.edu> <1995May06.181833.4006@berkeley.edu> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: Netscape 1.1N Lines: 8 In article <1995May06.181833.4006@berkeley.edu>, atanaka@berkeley.edu (Aiko Tanaka) writes: > I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. 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. -- Jen Moreno -- Universidad Nacional Autónoma de México (DGSCA) "The hatch is open. Is anyone listening?" From elaurent@pacbell.net Mon May 08 21:54:33 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!pacbell!elaurent From: elaurent@pacbell.net (Élodie Laurent) Newsgroups: comp.dsp Subject: Re: Question: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995May08.215433.3647@pacbell.net> Date: Mon, 08 May 1995 21:54:33 GMT References: <1995May06.080733.1580@illinois.edu> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: Netscape 1.1N Lines: 12 In article <1995May06.080733.1580@illinois.edu>, jfischer@illinois.edu (Jen Fischer) writes: > A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. > A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier. Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. Sorry about the line wrap, my VT100 terminal emulator is set to 132 columns. -- Élodie Laurent Zyxel U-1496E @ 28,800 bps "The hatch is open. Is anyone listening?" From astewart@earthlink.net Tue May 09 09:43:33 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!earthlink!astewart From: astewart@earthlink.net (Amy Stewart) Newsgroups: comp.dsp Subject: Re: Question: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995May09.094333.5586@earthlink.net> Date: Tue, 09 May 1995 09:43:33 GMT References: <1995May06.080733.1580@illinois.edu> <1995May06.181833.4006@berkeley.edu> <1995May07.171033.8319@unam.mx> Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995May07.171033.8319@unam.mx>, jmoreno@unam.mx (Jen Moreno) writes: > 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. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. -- Amy Stewart Opinions expressed are solely my own and not those of EarthLink Network. ------------------------------------------------------------