From nnakamura@netcom.com Fri Jan 19 01:13:20 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!netcom!nnakamura From: nnakamura@netcom.com (Nadine Nakamura) Newsgroups: comp.dsp Subject: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Jan19.011320.1708@netcom.com> Date: Fri, 19 Jan 1996 01:13:20 GMT Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: TIN [version 1.2 PL2] 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. -- Nadine Nakamura Tape trading list upon request. SASE required for international mail. From jsato@inria.fr Fri Jan 19 09:51:20 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!inria!jsato From: jsato@inria.fr (Julien Sato) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Jan19.095120.4030@inria.fr> Date: Fri, 19 Jan 1996 09:51:20 GMT References: <1996Jan19.011320.1708@netcom.com> Organization: INRIA Rocquencourt NNTP-Posting-Host: inria.fr X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1996Jan19.011320.1708@netcom.com>, nnakamura@netcom.com (Nadine Nakamura) 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. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. -- Julien Sato | jsato@inria.fr PGP Key fingerprint: 224A FA45 199D AC30 "Keep the channels open." From mkang@netcom.com Sat Jan 20 21:14:20 1996 Path: ashpoly!cascade!bigsur!netcom!mkang From: mkang@netcom.com (Min-jun Kang) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Jan20.211420.4670@netcom.com> Date: Sat, 20 Jan 1996 21:14:20 GMT References: <1996Jan19.011320.1708@netcom.com> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: WinVN 0.99.5 Lines: 11 In article <1996Jan19.011320.1708@netcom.com>, nnakamura@netcom.com (Nadine Nakamura) writes: > Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. 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. Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! -- Min-jun Kang Hayes Optima 288 @ 19,200 bps "The hatch is open. Is anyone listening?" From mlaurent@hanse.de Sun Jan 21 05:00:20 1996 Path: ashpoly!cascade!transat!ukc!fennimore!hanse!mlaurent From: mlaurent@hanse.de (Mei Laurent) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Jan21.050020.6920@hanse.de> Date: Sun, 21 Jan 1996 05:00:20 GMT References: <1996Jan19.011320.1708@netcom.com> <1996Jan20.211420.4670@netcom.com> Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1996Jan20.211420.4670@netcom.com>, mkang@netcom.com (Min-jun Kang) 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. Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. -- Mei Laurent "5 sigma is a discovery. 7 is a question." Pentium 90 (OS/2 Warp) / NEXTSTEP 3.3