From lkim@mit.edu Wed Nov 01 23:16:07 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!mit!lkim From: lkim@mit.edu (Liam Kim) Newsgroups: comp.dsp Subject: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Nov01.231607.1457@mit.edu> Date: Wed, 01 Nov 1995 23:16:07 GMT Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: WinVN 0.99.5 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. 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. MATLAB script available upon request via email. -- Liam Kim "We don't sign stars. We build them." 486DX4/100 (FreeBSD 2.0.5) / TOS 4.04 From nweber@uu.net Fri Nov 03 00:03:07 1995 Path: ashpoly!cascade!bigsur!uu!nweber From: nweber@uu.net (Natalia Weber) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Nov03.000307.2535@uu.net> Date: Fri, 03 Nov 1995 00:03:07 GMT References: <1995Nov01.231607.1457@mit.edu> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1995Nov01.231607.1457@mit.edu>, lkim@mit.edu (Liam Kim) 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. 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. -- === Natalia Weber === Dept of Electrical Engineering, UUNET Technologies, Falls Church VA "Extraordinary claims require extraordinary spectra." From tsanchez@cam.ac.uk Sat Nov 04 00:13:07 1995 Path: ashpoly!cascade!brgate!saturno!cam!tsanchez From: tsanchez@cam.ac.uk (Tomas Sánchez) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Nov04.001307.2433@cam.ac.uk> Date: Sat, 04 Nov 1995 00:13:07 GMT References: <1995Nov01.231607.1457@mit.edu> <1995Nov03.000307.2535@uu.net> Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1995Nov03.000307.2535@uu.net>, nweber@uu.net (Natalia Weber) writes: > 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. 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. -- Tomas Sánchez Practical Peripherals 14.4 @ 33,600 bps "Hardware is temporary. The signal survives." From slee@mit.edu Sat Nov 04 13:42:07 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!mit!slee From: slee@mit.edu (Seo-yeon Lee) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Nov04.134207.2464@mit.edu> Date: Sat, 04 Nov 1995 13:42:07 GMT References: <1995Nov01.231607.1457@mit.edu> <1995Nov03.000307.2535@uu.net> <1995Nov04.001307.2433@cam.ac.uk> Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1995Nov04.001307.2433@cam.ac.uk>, tsanchez@cam.ac.uk (Tomas Sánchez) writes: > 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. 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. PGP Public key available via finger or upon request. -- Seo-yeon Lee Tape trading list upon request. SASE required for international mail. From ssato@uu.net Mon Nov 06 08:01:07 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!uu!ssato From: ssato@uu.net (Steve Sato) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Nov06.080107.2373@uu.net> Date: Mon, 06 Nov 1995 08:01:07 GMT References: <1995Nov01.231607.1457@mit.edu> <1995Nov03.000307.2535@uu.net> <1995Nov04.001307.2433@cam.ac.uk> <1995Nov04.134207.2464@mit.edu> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1995Nov04.134207.2464@mit.edu>, slee@mit.edu (Seo-yeon Lee) writes: > 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. > PGP Public key available via finger or upon request. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. -- Steve Sato Opinions expressed are solely my own and not those of UUNET Technologies, Falls Church VA. ------------------------------------------------------------