From drodriguez@stanford.edu Tue Mar 19 18:18:21 1996 Path: ashpoly!cascade!bigsur!stanford!drodriguez From: drodriguez@stanford.edu (Diego Rodríguez) Newsgroups: comp.dsp Subject: Question: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Mar19.181821.1386@stanford.edu> Date: Tue, 19 Mar 1996 18:18:21 GMT Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 10 Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. A Kaiser-Bessel window with parameter beta = 8.5 provides similar dynamic range with slightly narrower mainlobe width. A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier. MATLAB script available upon request via email. -- Diego Rodríguez -- Stanford University Computer Systems Lab "Hardware is temporary. The signal survives." From msilva@pipeline.com Tue Mar 19 23:02:21 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!pipeline!msilva From: msilva@pipeline.com (Mei Silva) Newsgroups: comp.dsp Subject: Re: Question: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Mar19.230221.3192@pipeline.com> Date: Tue, 19 Mar 1996 23:02:21 GMT References: <1996Mar19.181821.1386@stanford.edu> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: NewsWatcher 2.0b24 Lines: 12 In article <1996Mar19.181821.1386@stanford.edu>, drodriguez@stanford.edu (Diego Rodríguez) writes: > Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. > 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. Top-posters will be placed in my ~/.killfile without notice. -- Mei Silva SupraFAXModem 28.8 @ 19,200 bps "When every node is whole, the channel opens." From hfournier@cern.ch Wed Mar 20 08:14:21 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!cern!hfournier From: hfournier@cern.ch (Hana Fournier) Newsgroups: comp.dsp Subject: Re: Question: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Mar20.081421.8865@cern.ch> Date: Wed, 20 Mar 1996 08:14:21 GMT References: <1996Mar19.181821.1386@stanford.edu> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1996Mar19.181821.1386@stanford.edu>, drodriguez@stanford.edu (Diego Rodríguez) writes: > Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. > A Kaiser-Bessel window with parameter beta = 8.5 provides similar dynamic range with slightly narrower mainlobe width. Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. -- Hana Fournier *PLONK* filter active for trolls. Acorn RiscPC 600 - NetBSD 1.0 From mtanaka@clari.net Wed Mar 20 19:51:21 1996 Path: ashpoly!cascade!transat!ukc!fennimore!clari!mtanaka From: mtanaka@clari.net (Matthias Tanaka) Newsgroups: comp.dsp Subject: Re: Question: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Mar20.195121.4285@clari.net> Date: Wed, 20 Mar 1996 19:51:21 GMT References: <1996Mar19.181821.1386@stanford.edu> <1996Mar20.081421.8865@cern.ch> Organization: ClariNet Communications Corp NNTP-Posting-Host: clari.net X-Newsreader: WinVN 0.99.5 Lines: 11 In article <1996Mar20.081421.8865@cern.ch>, hfournier@cern.ch (Hana Fournier) writes: > Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. Unsubscribe me from this list! (Wait, this is Usenet, never mind). -- Matthias Tanaka | mtanaka@clari.net PGP Key fingerprint: 8265 41A3 A144 E346 "Keep the channels open."