From lnakamura@pipeline.com Tue Mar 01 12:46:46 1994
Path: ashpoly!cascade!transat!sunet!nordrelay!pipeline!lnakamura
From: lnakamura@pipeline.com (Liam Nakamura)
Newsgroups: comp.dsp
Subject: Question: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1994Mar01.124646.9144@pipeline.com>
Date: Tue, 01 Mar 1994 12:46:46 GMT
Organization: The Pipeline Internet Network
NNTP-Posting-Host: pipeline.com
X-Newsreader: NewsWatcher 2.0b24
Lines: 10

Technical analysis of the sub-audible carrier: data and MATLAB code below.

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).

Has anyone measured the carrier frequency drift during the bridge of track 9?

-- 
Liam Nakamura
Tape trading list upon request. SASE required for international mail.

From blarsson@tum.de Wed Mar 02 09:51:46 1994
Path: ashpoly!cascade!transat!ukc!fennimore!tum!blarsson
From: blarsson@tum.de (Bastien Larsson)
Newsgroups: comp.dsp
Subject: Re: Question: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1994Mar02.095146.3152@tum.de>
Date: Wed, 02 Mar 1994 09:51:46 GMT
References: <1994Mar01.124646.9144@pipeline.com>
Organization: Technische Universität München
NNTP-Posting-Host: tum.de
X-Newsreader: WinVN 0.99.5
Lines: 11

In article <1994Mar01.124646.9144@pipeline.com>, lnakamura@pipeline.com (Liam Nakamura) writes:
> Technical analysis of the sub-audible carrier: data and MATLAB code below.
> A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics.

If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386.

Top-posters will be placed in my ~/.killfile without notice.

-- 
Bastien Larsson
Tape trading list upon request. SASE required for international mail.