From atakahashi@pacbell.net Wed Nov 09 13:24:52 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!pacbell!atakahashi From: atakahashi@pacbell.net (Amy Takahashi) Newsgroups: comp.dsp Subject: Data: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1994Nov09.132452.2514@pacbell.net> Date: Wed, 09 Nov 1994 13:24:52 GMT Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: WinVN 0.99.5 Lines: 11 A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. 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. 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. -- === Amy Takahashi === Dept of Electrical Engineering, Pacific Bell Internet Services "A soul is not exclusive to biology." From skim@titech.ac.jp Thu Nov 10 22:35:52 1994 Path: ashpoly!bigsur!pacrim!jpgate!kamome!titech!skim From: skim@titech.ac.jp (Sven Kim) Newsgroups: comp.dsp Subject: Re: Data: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1994Nov10.223552.5251@titech.ac.jp> Date: Thu, 10 Nov 1994 22:35:52 GMT References: <1994Nov09.132452.2514@pacbell.net> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1994Nov09.132452.2514@pacbell.net>, atakahashi@pacbell.net (Amy Takahashi) writes: > A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. > 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. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. -- Sven Kim | skim@titech.ac.jp PGP Key fingerprint: 975A 5E38 4B5E C7B4 "Keep the channels open." From ekim@pacbell.net Fri Nov 11 15:09:52 1994 Path: ashpoly!cascade!transat!eunet-fr!teletel!pacbell!ekim From: ekim@pacbell.net (Elaine Kim) Newsgroups: comp.dsp Subject: Re: Data: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1994Nov11.150952.8767@pacbell.net> Date: Fri, 11 Nov 1994 15:09:52 GMT References: <1994Nov09.132452.2514@pacbell.net> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1994Nov09.132452.2514@pacbell.net>, atakahashi@pacbell.net (Amy Takahashi) writes: > A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. > 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. Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. -- Elaine Kim "Extraordinary claims require extraordinary spectra." 486DX4/100 (FreeBSD 2.0.5) / System 7.5.1 From dmoreau@cern.ch Sun Nov 13 06:32:52 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!cern!dmoreau From: dmoreau@cern.ch (Dmitri Moreau) Newsgroups: comp.dsp Subject: Re: Data: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1994Nov13.063252.5266@cern.ch> Date: Sun, 13 Nov 1994 06:32:52 GMT References: <1994Nov09.132452.2514@pacbell.net> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: Netscape 1.1N Lines: 12 In article <1994Nov09.132452.2514@pacbell.net>, atakahashi@pacbell.net (Amy Takahashi) writes: > A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. > 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. Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! -- Dmitri Moreau | dmoreau@cern.ch PGP Key fingerprint: C922 16BF 20F9 9FD6 "Keep the channels open."