From hfischer@utexas.edu Fri Sep 16 04:42:22 1994 Path: ashpoly!cascade!bigsur!utexas!hfischer From: hfischer@utexas.edu (Hugo Fischer) Newsgroups: comp.dsp Subject: DBPSK demodulation of the 0.71 baud Stardust telemetry stream Message-ID: <1994Sep16.044222.8079@utexas.edu> Date: Fri, 16 Sep 1994 04:42:22 GMT Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 11 Differential Binary Phase Shift Keying (DBPSK) parameter extraction results. Each message frame begins with an 8-bit Barker sequence [11100010] for frame synchronization. Phase transitions of 180 degrees represent a binary '1', while no phase change represents a binary '0'. Has anyone encountered bit errors in their decoded text? The Golay decoder corrects up to 3 bit errors per 24-bit codeword. -- === Hugo Fischer === Dept of Electrical Engineering, University of Texas at Austin "A soul is not exclusive to biology." From cvasiliev@kiae.su Fri Sep 16 21:44:22 1994 Path: ashpoly!cascade!bigsur!kiae!cvasiliev From: cvasiliev@kiae.su (Callum Vasiliev) Newsgroups: comp.dsp Subject: Re: DBPSK demodulation of the 0.71 baud Stardust telemetry stream Message-ID: <1994Sep16.214422.8286@kiae.su> Date: Fri, 16 Sep 1994 21:44:22 GMT References: <1994Sep16.044222.8079@utexas.edu> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1994Sep16.044222.8079@utexas.edu>, hfischer@utexas.edu (Hugo Fischer) writes: > Differential Binary Phase Shift Keying (DBPSK) parameter extraction results. > Each message frame begins with an 8-bit Barker sequence [11100010] for frame synchronization. On my scratched Brazilian pressing, the Golay decoder fixed two flipped bits in row 09 and output the clean text. -- Callum Vasiliev US Robotics Courier V.34 @ 28,800 bps "There are 14 nodes and only 10 countries. Count again."