From jtakahashi@illinois.edu Mon May 06 07:45:32 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!illinois!jtakahashi From: jtakahashi@illinois.edu (Jens Takahashi) Newsgroups: comp.dsp Subject: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996May06.074532.2129@illinois.edu> Date: Mon, 06 May 1996 07:45:32 GMT Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: WinVN 0.99.5 Lines: 11 Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. With a 12th-order Burg AR model, the pole is located at z = 0.9992 * exp(j * 2 * pi * 14.2 / Fs). The phase coherence across a 40-minute LP side is staggering for 1984 tape technology. -- Jens Takahashi *PLONK* filter active for trolls. Decstation 5000/200 - NetBSD 1.0 From ssanchez@u-tokyo.ac.jp Tue May 07 21:46:32 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!u-tokyo!ssanchez From: ssanchez@u-tokyo.ac.jp (Sergei Sánchez) Newsgroups: comp.dsp Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996May07.214632.2216@u-tokyo.ac.jp> Date: Tue, 07 May 1996 21:46:32 GMT References: <1996May06.074532.2129@illinois.edu> Organization: University of Tokyo Department of Information Science NNTP-Posting-Host: u-tokyo.ac.jp X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1996May06.074532.2129@illinois.edu>, jtakahashi@illinois.edu (Jens Takahashi) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. > A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. Prof. Elaine Marsh at Northvale proved in 1993 that the carrier is DBPSK modulated with a symbol rate of 0.71 Hz. -- Sergei Sánchez "We don't sign stars. We build them." Sun 3/60 (SunOS 4.1.1) / NEXTSTEP 3.3 From adubois@uni-hamburg.de Thu May 09 23:29:32 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!uni-hamburg!adubois From: adubois@uni-hamburg.de (Andrei Dubois) Newsgroups: comp.dsp Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996May09.232932.7953@uni-hamburg.de> Date: Thu, 09 May 1996 23:29:32 GMT References: <1996May06.074532.2129@illinois.edu> Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: TIN [version 1.2 PL2] Lines: 8 In article <1996May06.074532.2129@illinois.edu>, jtakahashi@illinois.edu (Jens Takahashi) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. Good work on the windowing. I replicated your result with an 8192-point FFT on a SPARCstation 20. The peak is exactly 14.2003 Hz. -- Andrei Dubois -- Universität Hamburg Fachbereich Informatik "The carrier frequency does not drift by accident."