A dynamic bp decoding method for local different signs for ldpc codes

Abstract

The invention provides a local dynamic update decoding method (LILRBP) based on an LDPC code aiming at a dynamic BP decoding algorithm of the LDPC code. According to the method, the local residual based message update is adopted, the BP decoding performance including a small number of iterations under high signal-to-noise ratio can be effectively improved, and other dynamic BP decoding algorithms can be surpassed. Different from the previous dynamic BP decoding methods, the LILRBP method considers that residuals have time validity, and therefore, the LILRBP method only focuses on the recent part of the residuals, sets an iteration times threshold, then filters the local residuals according to the change of likelihood ratio symbols of a correlation variable node below the threshold, and then determines the next message to be updated according to the filtered residual; and above the threshold, the next message to be updated is directly determined based on the local residual. The advantages of the method are as follows: the message update can always be performed by using the latest messages, the role of accelerating the algorithm convergence speed can be played, and the local residuals are re-filtered below the threshold, the algorithm convergence can be further accelerated, the convergence of the algorithm can be influenced by the combination of the two operations, the convergence speed of the BP decoding algorithm can be effectively improved, and the purpose of improving the decoding performance can be achieved.

Description

technical field [0001] The invention relates to the technical field of LDPC code decoding, in particular to a dynamic decoding method for local different numbers based on LDPC codes. Background technique [0002] Since the LDPC code was discovered again in 1996, its decoding algorithm (flooding BP algorithm) has become the focus of the field of encoding and decoding because of its simple implementation and linear increase in decoding complexity. The dynamic BP decoding algorithm represented by the SVNF-RBP algorithm increases the residual calculation and search complexity, but also greatly improves the decoding performance of the BP algorithm. [0003] The SVNF-RBP decoding algorithm is an asynchronous dynamic message iterative algorithm, each time according to a largest check node to variable node message residual, locate the next check node to variable node message to be updated. The message update is based on the order of the largest residual found each time, and is pass...

AI Technical Summary

Problems solved by technology

The SVNF-RBP algorithm can greatly improve the performance of BP decoding, but it increases a lot of calculation and search complexity

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