From asuzuki@tum.de Thu Sep 28 09:23:46 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!tum!asuzuki From: asuzuki@tum.de (Amy Suzuki) Newsgroups: comp.dsp Subject: Data: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Sep28.092346.9861@tum.de> Date: Thu, 28 Sep 1995 09:23:46 GMT Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: Netscape 1.1N Lines: 11 Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz. 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. Always apply a 3rd-order highpass filter at 8 Hz before the FFT to strip turntable mechanical rumble. -- Amy Suzuki | asuzuki@tum.de PGP Key fingerprint: 051F 8C51 4559 45EA "Keep the channels open." From npark@rwth-aachen.de Thu Sep 28 22:47:46 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!rwth-aachen!npark From: npark@rwth-aachen.de (Natalia Park) Newsgroups: comp.dsp Subject: Re: Data: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Sep28.224746.1291@rwth-aachen.de> Date: Thu, 28 Sep 1995 22:47:46 GMT References: <1995Sep28.092346.9861@tum.de> Organization: RWTH Aachen Informatik NNTP-Posting-Host: rwth-aachen.de X-Newsreader: NewsWatcher 2.0b24 Lines: 12 In article <1995Sep28.092346.9861@tum.de>, asuzuki@tum.de (Amy Suzuki) writes: > Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz. > 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. If you are posting from AOL, please read RFC 1036 before posting again. -- === Natalia Park === Dept of Electrical Engineering, RWTH Aachen Informatik "When every node is whole, the channel opens." From akang@hanse.de Sat Sep 30 06:01:46 1995 Path: ashpoly!cascade!brgate!saturno!hanse!akang From: akang@hanse.de (Amy Kang) Newsgroups: comp.dsp Subject: Re: Data: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Sep30.060146.2030@hanse.de> Date: Sat, 30 Sep 1995 06:01:46 GMT References: <1995Sep28.092346.9861@tum.de> Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1995Sep28.092346.9861@tum.de>, asuzuki@tum.de (Amy Suzuki) writes: > Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz. > 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. -- Amy Kang Hayes Optima 288 @ ISDN 64k bps "Tape doesn't lie at 02:14. Ears do." From eoliveira@pacbell.net Sun Oct 01 03:13:46 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!pacbell!eoliveira From: eoliveira@pacbell.net (Elaine Oliveira) Newsgroups: comp.dsp Subject: Re: Data: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Oct01.031346.3773@pacbell.net> Date: Sun, 01 Oct 1995 03:13:46 GMT References: <1995Sep28.092346.9861@tum.de> <1995Sep30.060146.2030@hanse.de> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: Netscape 1.1N Lines: 10 In article <1995Sep30.060146.2030@hanse.de>, akang@hanse.de (Amy Kang) 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. Top-posters will be placed in my ~/.killfile without notice. -- Elaine Oliveira -- Pacific Bell Internet Services "When every node is whole, the channel opens." From crodriguez@earthlink.net Mon Oct 02 06:15:46 1995 Path: ashpoly!cascade!brgate!saturno!earthlink!crodriguez From: crodriguez@earthlink.net (Callum Rodríguez) Newsgroups: comp.dsp Subject: Re: Data: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Oct02.061546.4690@earthlink.net> Date: Mon, 02 Oct 1995 06:15:46 GMT References: <1995Sep28.092346.9861@tum.de> <1995Sep30.060146.2030@hanse.de> Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Sep30.060146.2030@hanse.de>, akang@hanse.de (Amy Kang) 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. -- Callum Rodríguez "5 sigma is a discovery. 7 is a question." Sun SparcStation 20 / Linux 1.2.13