EEE 1001 022 Bootstrapped Low Complexity Iterative Decoding Algorithm (original) (raw)

Bootstrapped Iterative Decoding Algorithms for Low Density Parity Check (LDPC) Codes

2010

Reliability ratio based weighted bit-flipping algorithm is one of the best hard decision decoding algorithms in performance. Recently several modifications are done to this technique either to improve performance or to lower the complexity. The implementation efficient reliability ratio based weighted bit-flipping is developed targeting decreasing processing time of the decoding process. In this paper we are targeting improving performance of recent developed algorithm named low complex implementation efficient reliability ratio based weighted bit-flipping by adding a bootstrap step to the decoding technique which leads to increase in reliability of received bits then number of decoded bits will be increased leading to improve in performance. Also a modification done to bootstrap step for further increase the performance.

Reliability ratio based weighted bit-flipping decoding for low-density parity-check codes

Electronics Letters, 2004

In this contribution, a novel reliability-ratio based weighted bit-flipping(RRWBF) algorithm is proposed for decoding Low Density Parity Check (LDPC) codes. The RRWBF algorithm proposed is benchmarked against the conventional weighted bit-flipping (WBF) algorithm [1] and the improved weighted bit-flipping (IWBF) algorithm [2]. More than 1 and 2 dB coding gain was achieved at an BER of 10 −5 while invoking the RRWBF algorithm in comparison to the two benchmarking schemes, when communicating over an AWGN and an uncorrelated Rayleigh channel, respectively. Furthermore, the decoding complexity of the proposed RRWBF algorithm is maintained at the same level as that of the conventional WBF algorithm.

A New Reliability Ratio Weighted Bit Flipping Algorithm for Decoding LDPC Codes

Wirel. Commun. Mob. Comput., 2021

In this study, we propose a “New Reliability Ratio Weighted Bit Flipping” (NRRWBF) algorithm for Low-Density Parity-Check (LDPC) codes. This algorithm improves the “Reliability Ratio Weighted Bit Flipping” (RRWBF) algorithm by modifying the reliability ratio. It surpasses the RRWBF in performance, reaching a 0.6 dB coding gain at a Binary Error Rate (BER) of 10 over the Additive White Gaussian Noise (AWGN) channel, and presents a significant reduction in the decoding complexity. Furthermore, we improved NRRWBF using the sum of the syndromes as a criterion to avoid the infinite loop. This will enable the decoder to attain a more efficient and effective decoding performance.

Reliability-based schedule for bit-flipping decoding of low-density Parity-check codes

IEEE Transactions on Communications, 2004

A reliability-based message-passing schedule for iterative decoding of low-density parity-check codes is proposed. Simulation results for bit-flipping algorithms (with binary messages) show that a reliability-based schedule can provide considerable improvement in performance and decoding speed over the so-called flooding (parallel) schedule, as well as the existing graph-based schedules. The cost associated with this improvement is negligible and is equivalent to having a two-bit representation for initial messages, instead of the standard one bit for hard-decision algorithms, only at the first iteration (all the exchanged messages are still binary).

Hybrid weighted bit flipping low density parity check decoding

Digital Signal Processing, 2014

Error correction codes Low density parity check codes (LDPC) Parallel bit flipping Low density parity check codes (LDPC) exhibit near capacity performance in terms of error correction. Large hardware costs, limited flexibility in terms of code length/code rate and considerable power consumption limit the use of belief-propagation algorithm based LDPC decoders in area and energy sensitive mobile environment. Serial bit flipping algorithms offer a trade-off between resource utilization and error correction performance at the expense of increased number of decoding iterations required for convergence. Parallel weighted bit flipping decoding and its variants aim at reducing the decoding iteration and time by flipping the potential erroneous bits in parallel. However, in most of the existing parallel decoding methods, the flipping threshold requires complex computations. In this paper, Hybrid Weighted Bit Flipping (HWBF) decoding is proposed to allow multiple bit flipping in each decoding iteration. To compute the number of bits that can be flipped in parallel, a criterion for determining the relationship between the erroneous bits in received code word is proposed. Using the proposed relation the proposed scheme can detect and correct a maximum of 3 erreneous hard decision bits in an iteration. The simulation results show that as compared to existing serial bit flipping decoding methods, the number of iterations required for convergence is reduced by 45% and the decoding time is reduced by 40%, by the use of proposed HWBF decoding. As compared to existing parallel bit flipping decoding methods, the proposed HWBF decoding can achieve similar bit error rate (BER) with same number of iterations and lesser computational complexity. Due to reduced number of decoding iterations, less computational complexity and reduced decoding time, the proposed HWBF decoding can be useful in energy sensitive mobile platforms.

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

IEEE Transactions on Information Theory, 2005

In this correspondence, a new method for improving hard-decision bit-flipping decoding of low-density parity-check (LDPC) codes is presented. Bits with a number of unsatisfied check sums larger than a predetermined threshold are flipped with a probability 1 which is independent of the code considered. The probability is incremented during decoding according to some rule. With a proper choice of the initial , the proposed improved bit-flipping (BF) algorithm achieves gain not only in performance, but also in average decoding time for signal-to-noise ratio (SNR) values of interest with respect to = 1.

IJERT-BER Performance Comparison of Bit Flipping Algorithms used for Decoding of LDPC Codes

International Journal of Engineering Research and Technology (IJERT), 2015

https://www.ijert.org/ber-performance-comparison-of-bit-flipping-algorithms-used-for-decoding-of-ldpc-codes https://www.ijert.org/research/ber-performance-comparison-of-bit-flipping-algorithms-used-for-decoding-of-ldpc-codes-IJERTV4IS051311.pdf In this paper the Bit Error Rate (BER) performance of different bit flipping algorithms used for decoding of Low Density Parity Check (LDPC) code is compared. These algorithms mainly depend on inversion function. Through simulation results the Noisy Gradient Descent Bit flipping (NGDBF) algorithm is proved to be best till date. This algorithm provides the best BER performance, for Smoothed Noisy Gradient Descent Bit flipping (SM-NGDBF) algorithm we can obtain BER 4.86×10-4 at 3.5db. The Multi Noisy Gradient Descent Bit flipping (M-NGDBF) algorithm requires the least number of iterations than the other algorithms proposed for decoding a codeword.

Iterative reliability-based decoding of low-density parity check codes

IEEE Journal on Selected Areas in Communications, 2001

In this paper, reliability based decoding is combined with belief propagation (BP) decoding for low-density parity check (LDPC) codes. At each iteration, the soft output values delivered by the BP algorithm are used as reliability values to perform reduced complexity soft decision decoding of the code considered. This approach allows to bridge the error performance gap between belief propagation decoding which remains suboptimum, and maximum likelihood decoding which is too complex to be implemented for the codes considered. Trade-offs between decoding complexity and error performance are also investigated. In particular, a stopping criterion which reduces the average number of iterations at the expense of very little performance degradation is proposed for this combined decoding approach. Simulations results for several Gallager LDPC codes and different set cyclic codes of hundreds of information bits are given and elaborated.

New low-density-parity-check decoding approach based on the hard and soft decisions algorithms

International Journal of Electrical and Computer Engineering (IJECE), 2023

It is proved that hard decision algorithms are more appropriate than a soft decision for low-density parity-check (LDPC) decoding since they are less complex at the decoding level. On the other hand, it is notable that the soft decision algorithm outperforms the hard decision one in terms of the bit error rate (BER) gap. In order to minimize the BER and the gap between these two families of LDPC codes, a new LDPC decoding algorithm is suggested in this paper, which is based on both the normalized min-sum (NMS) and modified-weighted bit-flipping (MWBF). The proposed algorithm is named normalized min sum-modified weighted bit flipping (NMSMWBF). The MWBF is executed after the NMS algorithm. The simulations show that our algorithm outperforms the NMS in terms of BER at 10-8 over the additive white gaussian noise (AWGN) channel by 0.25 dB. Furthermore, the proposed NMSMWBF and the NMS are both at the same level of decoding difficulty.