Journal of Nanjing University of Science and Technology

Modified LDPC BF Decoding Algorithm Based on Reliability Ratio

Qiang Guo

Published Jan 1, 2009• 0 citations

Abstract

Compared with belief-propagation decoding algorithm which has complexity class of o(n2),bit-flipping(BF) decoding algorithm for low density parity check(LDPC) codes has only complexity class of o(n).However,the performance of BF algorithm is degraded.This paper presents a modified BF decoding algorithm,which uses reliability ratio as a weight of information node in unsatisfied parity checks so that the soft information is introduced in decoding,and the decoding performance is improved greatly with a little more computation.Analyses show the modified algorithm still has a complexity class of o(n).Simulation results indicate that the error rate with 7dB SNR is improved from 10-3 of the weighted bit-flipping decoding algorithm to 10-4 of the modified algorithm.

Related papers

Self reliability based weighted bit-flipping decoding for low-density parity-check codes

Jin Sha, Minglun Gao, Zhongjin Zhang +2 more

Abstract- Low Density Parity Check (LDPC) codes can be decoded in various ways, namely the Bit-Flipping (BF) algorithm, the Weighted BF algorithm (WBF) ， the Belief Propagation (BP) algorithm and so on. These algorithms provide a wide range of tradeoffs among decoding complexity, decoding speed, and error rate performance. In this paper, a novel self-reliability-based weighted bit-flipping decoding scheme for low-density parity-check codes is proposed. Improvement in performance is observed in comparison with the modified weighted bit-flipping decoding scheme, and the decoding complexity can be significantly reduced as well. Key-Words:- Low-density parity-check (LDPC) codes, decoding algorithm, bit flipping, self reliability

International Conference on Instrumentation, Measurement, Circuits and SystemsApr 16, 20063 citations

An efficient bit-flipping decoding algorithm for LDPC codes

Tso-Cho Chen

In this paper, a new method for improving hard-decision bit-flipping (BF) decoding is proposed for low-density parity-check codes. The flipping criterion is derived theoretically from the soft-decision belief-propagation decoding algorithm. The proposed BF decoding algorithm is channel independent and is improved by introducing a more efficient method for computing the reliability of the parity checks. Extensive simulations are provided to demonstrate the efficiency of the proposed algorithm. Simulation results show that the proposed algorithm can achieve about 1.5dB coding gain improvement at BER = 5×10−6while reducing up to 48% iterations for decoding and maintaining low decoding complexity, compared with the conventional weighted BF algorithm.

Cross Strait Quad-Regional Radio Science and Wireless Technology Conference (CSQRWC)Jul 1, 20126 citations

An Improved Multi-bit Flipping Algorithm for LDPC Decoding

Lan Tang

The bit-flipping(BF) algorithm of low density parity check(LDPC) code has low computation complexity and great practicability.On the basis of studying simple BF,WBF and RRWBF,an improved BF algorithm is proposed on considering the reliability ratio and absolute value of symbol.The proposed algorithm flips more than one bit in each iteration.Simulation results indicate that compared with RRWBF,the error rate of the proposed algorithm with 5 dB is improved from 10-3 to 10-4.

Modern Electronics TechniqueJan 1, 20110 citations

Channel-independent weighted bit-flipping decoding algorithm for low-density parity-check codes

T.-C. Chen

In this study, a new method for improving hard-decision bit-flipping (BF) decoding is proposed for low-density parity-check codes. The flipping criterion is derived theoretically from the soft-decision belief-propagation decoding algorithm. The proposed BF decoding algorithm is channel independent and is improved by introducing a more efficient method for computing the reliability of the parity checks. Extensive simulations are provided to demonstrate the efficiency of the proposed algorithm. Simulation results show that the proposed algorithm can achieve about 1.6 dB coding gain improvement at BER=10−5 while reducing up to 53% iterations for decoding and maintaining low-decoding complexity, compared with the conventional weighted BF algorithm.

IET CommunicationsNov 27, 201210 citations

Modified Bit-Flipping Decoding of Low-Density Parity-Check Codes

Yuan Hua Liu, Mei Ling Zhang

A novel bit-flipping (BF) algorithm with low complexity for high-throughput decoding of low-density parity-check (LDPC) codes is presented. At each iteration, a novel threshold pattern is used to determine the code bits whether to be flipped or not, and the flipping error probability is effectively decreased. Compared with the weighted BF algorithm and its modifications, the modified BF algorithm has significantly lower complexity and decoding time. Through simulations the proposed BF algorithm is shown to achieve excellent performance and fast convergence speed while maintaining significantly low complexity thus facilitating high-throughput decoding.

Advanced materials researchJun 1, 20130 citations

New Weighted Bit-Flipping Decoding Algorithm for LDPC Codes

Zi-jian Dong, Tiecheng Song

Several Weighted BF (WBF) algorithms are investigated in this paper, and a novel modified reliability-ratio based WBF (MRWBF) decoding algorithm for LDPC codes is proposed.WBF algorithm considers the influence of parity information on the error metric.Based on WBF, the improved WBF (IWBF) algorithm further uses the feature of message reliability on the symbol decision.The reliability-ratio based WBF (RRWBF) can eliminate the defect of requiring off-line pre-processing in IWBF.Our proposed MRWBF further removes the step of calculating normalized weighted parameters in RRWBF and achieves more reduction in decoding complexity.The results of simulations show that the proposed algorithm is feasible, effective, and can achieve good decoding performance.

Advances in intelligent systems research/Advances in Intelligent Systems ResearchJan 1, 20134 citations