From mrobertson@kiae.su Sun Nov 03 05:18:46 1996 Path: ashpoly!cascade!brgate!saturno!kiae!mrobertson From: mrobertson@kiae.su (Mike Robertson) Newsgroups: comp.dsp Subject: Discussion: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Nov03.051846.9550@kiae.su> Date: Sun, 03 Nov 1996 05:18:46 GMT Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: Netscape 1.1N 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. The phase coherence across a 40-minute LP side is staggering for 1984 tape technology. -- Mike Robertson "Do not worship the copy." Atari TT030 / Linux 1.2.13 From enilsson@rwth-aachen.de Mon Nov 04 00:55:46 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!rwth-aachen!enilsson From: enilsson@rwth-aachen.de (Elaine Nilsson) Newsgroups: comp.dsp Subject: Re: Discussion: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Nov04.005546.8924@rwth-aachen.de> Date: Mon, 04 Nov 1996 00:55:46 GMT References: <1996Nov03.051846.9550@kiae.su> Organization: RWTH Aachen Informatik NNTP-Posting-Host: rwth-aachen.de X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1996Nov03.051846.9550@kiae.su>, mrobertson@kiae.su (Mike Robertson) 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). Have you checked your sound card's ADC clock? Cheap Sound Blaster cards use uncalibrated ceramic resonators that drift with temperature. -- Elaine Nilsson -- RWTH Aachen Informatik "The hatch is open. Is anyone listening?" From nhernandez@rwth-aachen.de Tue Nov 05 17:32:46 1996 Path: ashpoly!cascade!mxgate!coyoacan!rwth-aachen!nhernandez From: nhernandez@rwth-aachen.de (Nadine Hernández) Newsgroups: comp.dsp Subject: Re: Discussion: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Nov05.173246.3342@rwth-aachen.de> Date: Tue, 05 Nov 1996 17:32:46 GMT References: <1996Nov03.051846.9550@kiae.su> Organization: RWTH Aachen Informatik NNTP-Posting-Host: rwth-aachen.de X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Nov03.051846.9550@kiae.su>, mrobertson@kiae.su (Mike Robertson) 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). If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. -- Nadine Hernández Tape trading list upon request. SASE required for international mail.