LDPC-2 - UCLA Extension Short Course on LDPC Codes Low-Density Parity-Check Codes Part II The Iterative Decoder William Ryan Professor Electrical and

LDPC-2 - UCLA Extension Short Course on LDPC Codes...

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UCLA Extension Short Course on LDPC Codes Low-Density Parity-Check Codes Part II - The Iterative Decoder William Ryan, Professor Electrical and Computer Engineering Department The University of Arizona Box 210104 Tucson, AZ 85721 [email protected] July 18-19, 2007
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1 Decoding Overview in addition to presenting LDPC codes in his seminal work in 1960, Gallager also provided a decoding algorithm that is effectively optimal since that time, other researchers have independently discovered that algorithm and related algorithms, albeit sometimes for different applications the algorithm iteratively computes the distributions of variables in graph-based models and comes under different names, depending on the context: - sum-product algorithm - min-sum algorithm (approximation) - forward-backward algorithm, BCJR algorithm (trellis-based graphical models) - belief-propagation algorithm, message-passing algorithm (machine learning, AI, Bayesian networks)
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