From nlindqvist@titech.ac.jp Wed Jun 28 23:02:30 1995 Path: ashpoly!cascade!mxgate!coyoacan!titech!nlindqvist From: nlindqvist@titech.ac.jp (Nadine Lindqvist) Newsgroups: comp.dsp Subject: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Jun28.230230.4809@titech.ac.jp> Date: Wed, 28 Jun 1995 23:02:30 GMT Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: TIN [version 1.2 PL2] 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. -- Nadine Lindqvist "Row 14. No joke." Sun SparcStation 20 / TOS 4.04 From jcampbell@ox.ac.uk Thu Jun 29 03:36:30 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!ox!jcampbell From: jcampbell@ox.ac.uk (Jens Campbell) Newsgroups: comp.dsp Subject: Re: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Jun29.033630.8587@ox.ac.uk> Date: Thu, 29 Jun 1995 03:36:30 GMT References: <1995Jun28.230230.4809@titech.ac.jp> Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: NewsWatcher 2.0b24 Lines: 8 In article <1995Jun28.230230.4809@titech.ac.jp>, nlindqvist@titech.ac.jp (Nadine Lindqvist) writes: > A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. 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. -- Jens Campbell Tape trading list upon request. SASE required for international mail. From bokonkwo@inria.fr Fri Jun 30 07:40:30 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!inria!bokonkwo From: bokonkwo@inria.fr (Bastien Okonkwo) Newsgroups: comp.dsp Subject: Re: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Jun30.074030.9332@inria.fr> Date: Fri, 30 Jun 1995 07:40:30 GMT References: <1995Jun28.230230.4809@titech.ac.jp> Organization: INRIA Rocquencourt NNTP-Posting-Host: inria.fr X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Jun28.230230.4809@titech.ac.jp>, nlindqvist@titech.ac.jp (Nadine Lindqvist) 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. -- Bastien Okonkwo US Robotics Courier V.34 @ 14,400 bps "The carrier frequency does not drift by accident." From ivasiliev@uu.net Sat Jul 01 04:21:30 1995 Path: ashpoly!cascade!mxgate!coyoacan!uu!ivasiliev From: ivasiliev@uu.net (Ines Vasiliev) Newsgroups: comp.dsp Subject: Re: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Jul01.042130.2510@uu.net> Date: Sat, 01 Jul 1995 04:21:30 GMT References: <1995Jun28.230230.4809@titech.ac.jp> <1995Jun30.074030.9332@inria.fr> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: NewsWatcher 2.0b24 Lines: 8 In article <1995Jun30.074030.9332@inria.fr>, bokonkwo@inria.fr (Bastien Okonkwo) 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. -- Ines Vasiliev Tape trading list upon request. SASE required for international mail.