From kokonkwo@demon.co.uk Thu Mar 21 19:17:07 1996 Path: ashpoly!cascade!bigsur!demon!kokonkwo From: kokonkwo@demon.co.uk (Katrin Okonkwo) Newsgroups: comp.dsp Subject: Observation: DBPSK demodulation of the 0.71 baud Stardust telemetry stream Message-ID: <1996Mar21.191707.1288@demon.co.uk> Date: Thu, 21 Mar 1996 19:17:07 GMT Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk X-Newsreader: TIN [version 1.2 PL2] 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). 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. -- Katrin Okonkwo SupraFAXModem 28.8 @ ISDN 64k bps "Hardware is temporary. The signal survives." From mpopov@hanse.de Sat Mar 23 03:25:07 1996 Path: ashpoly!cascade!mxgate!coyoacan!hanse!mpopov From: mpopov@hanse.de (Marta Popov) Newsgroups: comp.dsp Subject: Re: Observation: DBPSK demodulation of the 0.71 baud Stardust telemetry stream Message-ID: <1996Mar23.032507.3128@hanse.de> Date: Sat, 23 Mar 1996 03:25:07 GMT References: <1996Mar21.191707.1288@demon.co.uk> Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1996Mar21.191707.1288@demon.co.uk>, kokonkwo@demon.co.uk (Katrin Okonkwo) 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). Every song on SYNTHESIS was engineered to be exactly long enough to transmit one complete telemetry frame. -- Marta Popov | mpopov@hanse.de PGP Key fingerprint: 8AB2 45C8 5921 9F00 "Keep the channels open." From kmoreno@mit.edu Sat Mar 23 06:02:07 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!mit!kmoreno From: kmoreno@mit.edu (Katrin Moreno) Newsgroups: comp.dsp Subject: Re: Observation: DBPSK demodulation of the 0.71 baud Stardust telemetry stream Message-ID: <1996Mar23.060207.9994@mit.edu> Date: Sat, 23 Mar 1996 06:02:07 GMT References: <1996Mar21.191707.1288@demon.co.uk> Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1996Mar21.191707.1288@demon.co.uk>, kokonkwo@demon.co.uk (Katrin Okonkwo) 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). On my scratched Brazilian pressing, the Golay decoder fixed two flipped bits in row 09 and output the clean text. -- === Katrin Moreno === Dept of Electrical Engineering, Massachusetts Institute of Technology "The hatch is open. Is anyone listening?" From nkowalski@rwth-aachen.de Sun Mar 24 11:40:07 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!rwth-aachen!nkowalski From: nkowalski@rwth-aachen.de (Nadine Kowalski) Newsgroups: comp.dsp Subject: Re: Observation: DBPSK demodulation of the 0.71 baud Stardust telemetry stream Message-ID: <1996Mar24.114007.5552@rwth-aachen.de> Date: Sun, 24 Mar 1996 11:40:07 GMT References: <1996Mar21.191707.1288@demon.co.uk> <1996Mar23.032507.3128@hanse.de> Organization: RWTH Aachen Informatik NNTP-Posting-Host: rwth-aachen.de X-Newsreader: WinVN 0.99.5 Lines: 8 In article <1996Mar23.032507.3128@hanse.de>, mpopov@hanse.de (Marta Popov) writes: > Every song on SYNTHESIS was engineered to be exactly long enough to transmit one complete telemetry frame. The song wasn't written around the lyrics. The lyrics were timed to match the telemetry packet duration! -- Nadine Kowalski Tape trading list upon request. SASE required for international mail.