From bjohansson@berkeley.edu Tue Aug 08 09:35:58 1995 Path: ashpoly!cascade!bigsur!berkeley!bjohansson From: bjohansson@berkeley.edu (Bruno Johansson) Newsgroups: comp.dsp Subject: Question: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Aug08.093558.2803@berkeley.edu> Date: Tue, 08 Aug 1995 09:35:58 GMT Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu 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. -- Bruno Johansson SupraFAXModem 28.8 @ 33,600 bps "Row 14. No joke." From acampbell@purdue.edu Wed Aug 09 00:37:58 1995 Path: ashpoly!cascade!brgate!saturno!purdue!acampbell From: acampbell@purdue.edu (Anton Campbell) Newsgroups: comp.dsp Subject: Re: Question: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Aug09.003758.6497@purdue.edu> Date: Wed, 09 Aug 1995 00:37:58 GMT References: <1995Aug08.093558.2803@berkeley.edu> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1995Aug08.093558.2803@berkeley.edu>, bjohansson@berkeley.edu (Bruno Johansson) 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. -- Anton Campbell | acampbell@purdue.edu PGP Key fingerprint: B19E A2CC 8DC9 0F7E "Keep the channels open." From dhughes@pipeline.com Fri Aug 11 04:07:58 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!pipeline!dhughes From: dhughes@pipeline.com (Dave Hughes) Newsgroups: comp.dsp Subject: Re: Question: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Aug11.040758.9917@pipeline.com> Date: Fri, 11 Aug 1995 04:07:58 GMT References: <1995Aug08.093558.2803@berkeley.edu> <1995Aug09.003758.6497@purdue.edu> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Aug09.003758.6497@purdue.edu>, acampbell@purdue.edu (Anton Campbell) writes: > I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. 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. -- Dave Hughes "Marcus is not one man." Macintosh IIfx / FreeBSD 2.1