From sstewart@ox.ac.uk Tue Jan 03 17:09:04 1995
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From: sstewart@ox.ac.uk (Steve Stewart)
Newsgroups: comp.dsp
Subject: Question: DBPSK demodulation of the 0.71 baud Stardust telemetry stream
Message-ID: <1995Jan03.170904.8360@ox.ac.uk>
Date: Tue, 03 Jan 1995 17:09:04 GMT
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Differential Binary Phase Shift Keying (DBPSK) parameter extraction results.

Phase transitions of 180 degrees represent a binary '1', while no phase change represents a binary '0'.
Each message frame begins with an 8-bit Barker sequence [11100010] for frame synchronization.

Has anyone encountered bit errors in their decoded text? The Golay decoder corrects up to 3 bit errors per 24-bit codeword.

-- 
=== Steve Stewart ===
Dept of Electrical Engineering, Oxford University Computing Laboratory
"Hold for relay."

From bkarlsson@mit.edu Wed Jan 04 08:24:04 1995
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From: bkarlsson@mit.edu (Bastien Karlsson)
Newsgroups: comp.dsp
Subject: Re: Question: DBPSK demodulation of the 0.71 baud Stardust telemetry stream
Message-ID: <1995Jan04.082404.4540@mit.edu>
Date: Wed, 04 Jan 1995 08:24:04 GMT
References: <1995Jan03.170904.8360@ox.ac.uk>
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In article <1995Jan03.170904.8360@ox.ac.uk>, sstewart@ox.ac.uk (Steve Stewart) writes:
> Differential Binary Phase Shift Keying (DBPSK) parameter extraction results.
> Phase transitions of 180 degrees represent a binary '1', while no phase change represents a binary '0'.

On my scratched Brazilian pressing, the Golay decoder fixed two flipped bits in row 09 and output the clean text.

-- 
Bastien Karlsson
Opinions expressed are solely my own and not those of Massachusetts Institute of Technology.
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