Simplified, presorted, syndrome-based, extended min-sum (EMS) decoding of non-binary LDPC codes

Abstract

Low complexity architecture for syndrome-based check node, SB- CN, processing in Extended Min-Sum, EMS, decoders for Non-Binary LDPC, NB-LDPC, codes using the principle of pre-sorting the variable messages based on a reliability criteria. Embodiments of the invention provide a check node processing unit (25) configured to determine at least one check node message to decode a signal encoded using aNB-LDPC code, the check node processing unit comprising: a data link to one or more message presorting units (24) configured to determine permuted variable node messages by applying one or more permutations to at least three variable node messages generated by one or more variable node processing units (23); a syndrome calculation unit (26) configured to determine a set of syndromes from the at least three permuted variable node messages, a syndrome comprising binary values; a decorrelation and permutation unit (27) configured, for each check node message of a given index, to: determine a permuted index by applying to said given index the inverse of the one or more permutations; select at least one valid syndrome in the set of syndromes, a valid syndrome comprising a binary value associated with said permuted index equal to a given value; determine, at least one candidate check node component from said at least one valid syndrome; a selection unit (28) configured to determine at least one check node message from said at least one candidate check node component.

Description

technical field [0001] The present invention relates generally to digital communications, and in particular to methods and apparatus for decoding signals encoded using error correcting codes. Background technique [0002] Error correcting codes are implemented in various data processing systems and devices to ensure protection of data from errors introduced during data transmission or storage in the presence of noise and / or interference. Encoding involves adding redundant data to the original data, which enables detection and / or correction of errors. [0003] Error correcting codes are implemented in a large number of devices and systems, for example in data communication or storage applications. Exemplary applications include voice and multimedia transmission, e.g., in wireless ad hoc networks (e.g., standardized in Wi-Fi 802.11), in radio communication systems (e.g., in 3G, 4G / LTE, 5G and later, etc. in), in optical communication systems, and in digital video broadcastin...

AI Technical Summary

Problems solved by technology

However, the calculation and ordering of syndromes introduces high complexity that increases with the number of messages processed by check node processing units, thus limiting the ability of syndrome-based architectures to process messages with high Application of coding rate

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