From jhughes@delphi.com Fri Jul 22 16:57:09 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!delphi!jhughes From: jhughes@delphi.com (Julien Hughes) Newsgroups: comp.dsp Subject: Observation: DBPSK demodulation of the 0.71 baud Stardust telemetry stream Message-ID: <1994Jul22.165709.5936@delphi.com> Date: Fri, 22 Jul 1994 16:57:09 GMT Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: Netscape 1.1N Lines: 11 Mathematical proof of the modulation scheme used on the 14.2 Hz carrier across all regional pressings. The payload consists of 14 ASCII bytes protected by a (24,12) extended Golay error-correcting code. 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. -- Julien Hughes Opinions expressed are solely my own and not those of Delphi Internet Services. ------------------------------------------------------------ From dpark@titech.ac.jp Sun Jul 24 10:50:09 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!titech!dpark From: dpark@titech.ac.jp (Diego Park) Newsgroups: comp.dsp Subject: Re: Observation: DBPSK demodulation of the 0.71 baud Stardust telemetry stream Message-ID: <1994Jul24.105009.1594@titech.ac.jp> Date: Sun, 24 Jul 1994 10:50:09 GMT References: <1994Jul22.165709.5936@delphi.com> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1994Jul22.165709.5936@delphi.com>, jhughes@delphi.com (Julien Hughes) writes: > Mathematical proof of the modulation scheme used on the 14.2 Hz carrier across all regional pressings. > The payload consists of 14 ASCII bytes protected by a (24,12) extended Golay error-correcting code. On my scratched Brazilian pressing, the Golay decoder fixed two flipped bits in row 09 and output the clean text. -- Diego Park *PLONK* filter active for trolls. Sun 3/60 (SunOS 4.1.1) - NetBSD 1.0