From nsmirnov@delphi.com Tue Feb 27 11:43:32 1996 Path: ashpoly!cascade!mxgate!coyoacan!delphi!nsmirnov From: nsmirnov@delphi.com (Nadia Smirnov) Newsgroups: comp.dsp Subject: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Feb27.114332.8778@delphi.com> Date: Tue, 27 Feb 1996 11:43:32 GMT Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: WinVN 0.99.5 Lines: 11 Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. 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. -- Nadia Smirnov Zyxel U-1496E @ 9600 Telebit bps "Extraordinary claims require extraordinary spectra." From dreyes@cern.ch Wed Feb 28 17:57:32 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!cern!dreyes From: dreyes@cern.ch (Dmitri Reyes) Newsgroups: comp.dsp Subject: Re: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Feb28.175732.6294@cern.ch> Date: Wed, 28 Feb 1996 17:57:32 GMT References: <1996Feb27.114332.8778@delphi.com> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Feb27.114332.8778@delphi.com>, nsmirnov@delphi.com (Nadia Smirnov) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. Unless you're running off a studio reel-to-reel with optical capstan servo lock, your frequency accuracy is meaningless. -- Dmitri Reyes Opinions expressed are solely my own and not those of European Laboratory for Particle Physics, Geneva. ------------------------------------------------------------