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NASA NTRS · 20060036498

(abstract) MCD3 - A Constraint Length 15 Viterbi Decoder

Buchanan, Jeff·Burke, Gary·Graham, Scott·Johnson, Robert·Kowalski, Jim·Nakahira, Sho·Stone, Earnest·Tung, Ramona·Whitaker, Bill
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Abstract

JPL is responsible for many space missions, as part of NASA's continuing unmanned exploration of the solar system. Signals from spacecraft at planetary distances arrive at Earth with poor S/N ratio. To reduce errors, the signals are encoded with an inner code of Viterbi encoding. One of the key parameters of Viterbi encoding is the constraint length. Previous space missions have used a constraint length of 7. Newer missions use 15, to give a considerably improved error correction ability. However, the complexity of the Viterbi decoder is increased so as to be 256 times more complex.

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Buchanan, Jeff, Burke, Gary, Graham, Scott, Johnson, Robert, Kowalski, Jim, Nakahira, Sho, Stone, Earnest, Tung, Ramona, Whitaker, Bill. 1996-09-08. (abstract) MCD3 - A Constraint Length 15 Viterbi Decoder. https://ntrs.nasa.gov/citations/20060036498

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