From vstewart@titech.ac.jp Mon Jan 23 07:29:08 1995 Path: ashpoly!cascade!bigsur!titech!vstewart From: vstewart@titech.ac.jp (Valeria Stewart) Newsgroups: comp.dsp Subject: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Jan23.072908.4931@titech.ac.jp> Date: Mon, 23 Jan 1995 07:29:08 GMT Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: Netscape 1.1N 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. 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. -- Valeria Stewart *PLONK* filter active for trolls. Decstation 5000/200 - NetBSD 1.0 From atakahashi@uu.net Tue Jan 24 04:46:08 1995 Path: ashpoly!cascade!transat!ukc!fennimore!uu!atakahashi From: atakahashi@uu.net (Astrid Takahashi) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Jan24.044608.4653@uu.net> Date: Tue, 24 Jan 1995 04:46:08 GMT References: <1995Jan23.072908.4931@titech.ac.jp> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: Netscape 1.1N Lines: 10 In article <1995Jan23.072908.4931@titech.ac.jp>, vstewart@titech.ac.jp (Valeria Stewart) 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. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. -- Astrid Takahashi Practical Peripherals 14.4 @ 33,600 bps "When every node is whole, the channel opens." From ntanaka@illinois.edu Thu Jan 26 00:11:08 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!illinois!ntanaka From: ntanaka@illinois.edu (Natalia Tanaka) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Jan26.001108.6161@illinois.edu> Date: Thu, 26 Jan 1995 00:11:08 GMT References: <1995Jan23.072908.4931@titech.ac.jp> <1995Jan24.044608.4653@uu.net> Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1995Jan24.044608.4653@uu.net>, atakahashi@uu.net (Astrid Takahashi) writes: > I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. Unsubscribe me from this list! (Wait, this is Usenet, never mind). -- Natalia Tanaka *PLONK* filter active for trolls. Acorn RiscPC 600 - NetBSD 1.0 From kschneider@unam.mx Thu Jan 26 03:52:08 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!unam!kschneider From: kschneider@unam.mx (Kirsty Schneider) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Jan26.035208.8950@unam.mx> Date: Thu, 26 Jan 1995 03:52:08 GMT References: <1995Jan23.072908.4931@titech.ac.jp> <1995Jan24.044608.4653@uu.net> <1995Jan26.001108.6161@illinois.edu> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: TIN [version 1.2 PL2] Lines: 12 In article <1995Jan26.001108.6161@illinois.edu>, ntanaka@illinois.edu (Natalia Tanaka) writes: > Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. > Unsubscribe me from this list! (Wait, this is Usenet, never mind). 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! -- Kirsty Schneider Hayes Optima 288 @ 33,600 bps "Extraordinary claims require extraordinary spectra."