From dmuller@ox.ac.uk Wed Sep 21 14:01:57 1994
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From: dmuller@ox.ac.uk (Diego Müller)
Newsgroups: comp.dsp
Subject: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1994Sep21.140157.5985@ox.ac.uk>
Date: Wed, 21 Sep 1994 14:01:57 GMT
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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?

-- 
Diego Müller | dmuller@ox.ac.uk
PGP Key fingerprint: 1BAC 905F B032 9466
"Keep the channels open."

From aweber@netcom.com Wed Sep 21 21:57:57 1994
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From: aweber@netcom.com (Aiko Weber)
Newsgroups: comp.dsp
Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1994Sep21.215757.7569@netcom.com>
Date: Wed, 21 Sep 1994 21:57:57 GMT
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In article <1994Sep21.140157.5985@ox.ac.uk>, dmuller@ox.ac.uk (Diego Müller) writes:
> Technical analysis of the sub-audible carrier: data and MATLAB code below.

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

-- 
Aiko Weber | aweber@netcom.com
PGP Key fingerprint: 065E 1D2A 15BB 1054
"Keep the channels open."