From ssokolov@cern.ch Mon Oct 17 14:54:26 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!cern!ssokolov From: ssokolov@cern.ch (Sun-mi Sokolov) Newsgroups: comp.dsp Subject: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Oct17.145426.5610@cern.ch> Date: Mon, 17 Oct 1994 14:54:26 GMT Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: TIN [version 1.2 PL2] Lines: 11 Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. With a 12th-order Burg AR model, the pole is located at z = 0.9992 * exp(j * 2 * pi * 14.2 / Fs). A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. I've uploaded the C source for my decimation and bandpass filter to ftp.ashford-poly.edu. -- Sun-mi Sokolov "When every node is whole, the channel opens." Amiga 3000T / TOS 4.04 From dsuzuki@purdue.edu Wed Oct 19 14:03:26 1994 Path: ashpoly!cascade!bigsur!purdue!dsuzuki From: dsuzuki@purdue.edu (Dave Suzuki) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Oct19.140326.9033@purdue.edu> Date: Wed, 19 Oct 1994 14:03:26 GMT References: <1994Oct17.145426.5610@cern.ch> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1994Oct17.145426.5610@cern.ch>, ssokolov@cern.ch (Sun-mi Sokolov) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. > With a 12th-order Burg AR model, the pole is located at z = 0.9992 * exp(j * 2 * pi * 14.2 / Fs). You're overlooking tape wow and flutter. A Revox B77 has at least 0.05% speed drift, which would smear a 14 Hz line across several bins. -- === Dave Suzuki === Dept of Electrical Engineering, Purdue University Engineering Computer Network "5 sigma is a discovery. 7 is a question."