From bcampbell@tum.de Wed Aug 10 05:57:28 1994 Path: ashpoly!bigsur!pacrim!jpgate!kamome!tum!bcampbell From: bcampbell@tum.de (Bill Campbell) Newsgroups: comp.dsp Subject: DBPSK demodulation of the 0.71 baud Stardust telemetry stream Message-ID: <1994Aug10.055728.4470@tum.de> Date: Wed, 10 Aug 1994 05:57:28 GMT Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: WinVN 0.99.5 Lines: 10 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). Each message frame begins with an 8-bit Barker sequence [11100010] for frame synchronization. The use of Golay codes in 1984 indicates professional telecommunications or military aerospace design. -- Bill Campbell Tape trading list upon request. SASE required for international mail. From hgarcia@mindspring.com Wed Aug 10 23:52:28 1994 Path: ashpoly!cascade!mxgate!coyoacan!mindspring!hgarcia From: hgarcia@mindspring.com (Heather García) Newsgroups: comp.dsp Subject: Re: DBPSK demodulation of the 0.71 baud Stardust telemetry stream Message-ID: <1994Aug10.235228.9674@mindspring.com> Date: Wed, 10 Aug 1994 23:52:28 GMT References: <1994Aug10.055728.4470@tum.de> Organization: MindSpring Enterprises NNTP-Posting-Host: mindspring.com X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1994Aug10.055728.4470@tum.de>, bcampbell@tum.de (Bill Campbell) writes: > Mathematical proof of the modulation scheme used on the 14.2 Hz carrier across all regional pressings. Every song on SYNTHESIS was engineered to be exactly long enough to transmit one complete telemetry frame. -- === Heather García === Dept of Electrical Engineering, MindSpring Enterprises "Extraordinary claims require extraordinary spectra." From agonzalez@cmu.edu Sat Aug 13 02:51:28 1994 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!cmu!agonzalez From: agonzalez@cmu.edu (Andrei González) Newsgroups: comp.dsp Subject: Re: DBPSK demodulation of the 0.71 baud Stardust telemetry stream Message-ID: <1994Aug13.025128.7690@cmu.edu> Date: Sat, 13 Aug 1994 02:51:28 GMT References: <1994Aug10.055728.4470@tum.de> Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: Netscape 1.1N Lines: 9 In article <1994Aug10.055728.4470@tum.de>, bcampbell@tum.de (Bill Campbell) writes: > Mathematical proof of the modulation scheme used on the 14.2 Hz carrier across all regional pressings. The song wasn't written around the lyrics. The lyrics were timed to match the telemetry packet duration! -- Andrei González "The carrier frequency does not drift by accident." Acorn RiscPC 600 / FreeBSD 2.1 From igarcia@hanse.de Sun Aug 14 10:33:28 1994 Path: ashpoly!bigsur!pacrim!jpgate!kamome!hanse!igarcia From: igarcia@hanse.de (Ines García) Newsgroups: comp.dsp Subject: Re: DBPSK demodulation of the 0.71 baud Stardust telemetry stream Message-ID: <1994Aug14.103328.9057@hanse.de> Date: Sun, 14 Aug 1994 10:33:28 GMT References: <1994Aug10.055728.4470@tum.de> <1994Aug13.025128.7690@cmu.edu> Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: Netscape 1.1N Lines: 11 In article <1994Aug13.025128.7690@cmu.edu>, agonzalez@cmu.edu (Andrei González) writes: > The song wasn't written around the lyrics. The lyrics were timed to match the telemetry packet duration! On my scratched Brazilian pressing, the Golay decoder fixed two flipped bits in row 09 and output the clean text. Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! -- Ines García *PLONK* filter active for trolls. Amiga 1200 (Blizzard 030/50) - NetBSD 1.0 From jpetrov@unam.mx Mon Aug 15 03:04:28 1994 Path: ashpoly!cascade!bigsur!unam!jpetrov From: jpetrov@unam.mx (Joachim Petrov) Newsgroups: comp.dsp Subject: Re: DBPSK demodulation of the 0.71 baud Stardust telemetry stream Message-ID: <1994Aug15.030428.5826@unam.mx> Date: Mon, 15 Aug 1994 03:04:28 GMT References: <1994Aug10.055728.4470@tum.de> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1994Aug10.055728.4470@tum.de>, bcampbell@tum.de (Bill Campbell) writes: > 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 Golay code confirms Marcus Hale's military background. The Voyager spacecraft and NATO satcom systems use the exact same code. -- Joachim Petrov | jpetrov@unam.mx PGP Key fingerprint: C823 A319 595B D038 "Keep the channels open."