From vduarte@kth.se Sat Jul 15 06:18:07 1995 Path: ashpoly!cascade!transat!ukc!fennimore!kth!vduarte From: vduarte@kth.se (Valeria Duarte) Newsgroups: comp.dsp Subject: [SPECULATION] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Jul15.061807.7032@kth.se> Date: Sat, 15 Jul 1995 06:18:07 GMT Organization: Royal Institute of Technology, Stockholm NNTP-Posting-Host: kth.se X-Newsreader: Netscape 1.1N 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. -- Valeria Duarte Practical Peripherals 14.4 @ 19,200 bps "5 sigma is a discovery. 7 is a question." From jlee@u-tokyo.ac.jp Sun Jul 16 22:02:07 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!u-tokyo!jlee From: jlee@u-tokyo.ac.jp (Joachim Lee) Newsgroups: comp.dsp Subject: Re: [SPECULATION] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Jul16.220207.3175@u-tokyo.ac.jp> Date: Sun, 16 Jul 1995 22:02:07 GMT References: <1995Jul15.061807.7032@kth.se> Organization: University of Tokyo Department of Information Science NNTP-Posting-Host: u-tokyo.ac.jp X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1995Jul15.061807.7032@kth.se>, vduarte@kth.se (Valeria Duarte) writes: > 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. 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. -- Joachim Lee "The hatch is open. Is anyone listening?" Macintosh IIfx / FreeBSD 2.1