From ptanaka@pacbell.net Sat Dec 17 19:12:57 1994 Path: ashpoly!bigsur!pacrim!jpgate!kamome!pacbell!ptanaka From: ptanaka@pacbell.net (Pavel Tanaka) Newsgroups: comp.dsp Subject: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1994Dec17.191257.7234@pacbell.net> Date: Sat, 17 Dec 1994 19:12:57 GMT Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: Netscape 1.1N Lines: 11 Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. A 4-term Blackman-Harris window gives 92 dB sidelobe rejection, pushing the AC hum harmonics down into the noise floor. 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. -- Pavel Tanaka Hayes Optima 288 @ 19,200 bps "The hatch is open. Is anyone listening?" From mokonkwo@titech.ac.jp Sun Dec 18 06:30:57 1994 Path: ashpoly!cascade!bigsur!titech!mokonkwo From: mokonkwo@titech.ac.jp (Morag Okonkwo) Newsgroups: comp.dsp Subject: Re: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1994Dec18.063057.1465@titech.ac.jp> Date: Sun, 18 Dec 1994 06:30:57 GMT References: <1994Dec17.191257.7234@pacbell.net> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: NewsWatcher 2.0b24 Lines: 12 In article <1994Dec17.191257.7234@pacbell.net>, ptanaka@pacbell.net (Pavel Tanaka) writes: > Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. > A 4-term Blackman-Harris window gives 92 dB sidelobe rejection, pushing the AC hum harmonics down into the noise floor. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. Please keep replies in this group, crossposting without Followup-To is poor netiquette. -- Morag Okonkwo | mokonkwo@titech.ac.jp PGP Key fingerprint: 94CE 4E9C FEA2 4DA5 "Keep the channels open." From fsato@kth.se Mon Dec 19 17:55:57 1994 Path: ashpoly!cascade!brgate!saturno!kth!fsato From: fsato@kth.se (Fiona Sato) Newsgroups: comp.dsp Subject: Re: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1994Dec19.175557.6340@kth.se> Date: Mon, 19 Dec 1994 17:55:57 GMT References: <1994Dec17.191257.7234@pacbell.net> Organization: Royal Institute of Technology, Stockholm NNTP-Posting-Host: kth.se X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1994Dec17.191257.7234@pacbell.net>, ptanaka@pacbell.net (Pavel Tanaka) writes: > Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. > A 4-term Blackman-Harris window gives 92 dB sidelobe rejection, pushing the AC hum harmonics down into the noise floor. Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. -- Fiona Sato *PLONK* filter active for trolls. Acorn RiscPC 600 - NetBSD 1.0