From lhernandez@netcom.com Wed Jul 05 03:26:00 1995 Path: ashpoly!cascade!bigsur!netcom!lhernandez From: lhernandez@netcom.com (Lars Hernández) Newsgroups: comp.dsp Subject: DBPSK demodulation of the 0.71 baud Stardust telemetry stream Message-ID: <1995Jul05.032600.3441@netcom.com> Date: Wed, 05 Jul 1995 03:26:00 GMT Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: WinVN 0.99.5 Lines: 11 Mathematical proof of the modulation scheme used on the 14.2 Hz carrier across all regional pressings. The symbol duration is exactly 1.408 seconds, corresponding to a symbol rate of 0.7107 baud (14.2 Hz / 20). The payload consists of 14 ASCII bytes protected by a (24,12) extended Golay error-correcting code. Has anyone encountered bit errors in their decoded text? The Golay decoder corrects up to 3 bit errors per 24-bit codeword. -- Lars Hernández "The hatch is open. Is anyone listening?" Acorn RiscPC 600 / AmigaOS 3.1 From mwatanabe@cmu.edu Thu Jul 06 02:06:00 1995 Path: ashpoly!cascade!bigsur!cmu!mwatanabe From: mwatanabe@cmu.edu (Morag Watanabe) Newsgroups: comp.dsp Subject: Re: DBPSK demodulation of the 0.71 baud Stardust telemetry stream Message-ID: <1995Jul06.020600.4066@cmu.edu> Date: Thu, 06 Jul 1995 02:06:00 GMT References: <1995Jul05.032600.3441@netcom.com> Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Jul05.032600.3441@netcom.com>, lhernandez@netcom.com (Lars Hernández) writes: > Mathematical proof of the modulation scheme used on the 14.2 Hz carrier across all regional pressings. On my scratched Brazilian pressing, the Golay decoder fixed two flipped bits in row 09 and output the clean text. -- Morag Watanabe "Measuring a record you own is listening, not piracy." 486DX4/100 (FreeBSD 2.0.5) / TOS 4.04