Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

An Overlapped Shuffled-BP LDPC Decoding Algorithm

Ya’nan Fan, Yao Xiujuan

Published Jan 1, 2016• 1 citation
OpenAlex

Abstract

Shuffled-BP (SBP) decoding algorithm is a variable-node-based serial decoding algorithm, which converges faster than the original Belief-Propagation (BP) decoding algorithm. However, due to the semi-parallel processing, there is a decrease in terms of convergence speed and error performance. An Overlapped Shuffled-BP(OSBP) decoding algorithm is proposed to enhance further the performance of the Shuffled-BP algorithm. In this algorithm, more than one sub-decoders are used to execute simultaneously, every sub-decoder has different updating order from each other. Regarding each variable node, the most reliable messages are kept and used for the next iteration, thus a faster convergence can be provided. Both theoretical analysis and simulation results show that, compared with SBP algorithm, OSBP algorithm possesses a better error performance as well as a higher convergence speed and introduces no extra storage requirement. Moreover, the proposed algorithm is effective for both regular and irregular LDPC codes.

Related papers

New group shuffled BP decoding algorithms for LDPC codes

Chi-Yuan Chang, Yu‐Liang Chen, Chang‐Ming Lee +1 more

Implementing a belief propagation (BP) based LDPC decoder requires high degrees of parallelism using many component soft-in soft-output (SISO) decoding units to perform message passing from variable nodes to check nodes or vice versa. An obvious complexity-reduction solution is to serialize the decoding process, i.e., dividing a decoding iteration into several serial sub-iterations in which a sub-iteration performs only part of the complete parallel message-passing operation. The group horizontal shuffled BP (GHSBP) and vertical shuffled BP (GVSBP) algorithms respectively partition the check and variable nodes of the code graph into groups to perform group-by-group message-passing decoding. This paper proposes new techniques to improve three key elements of a GHSBP decoding algorithm, namely, the grouping method, the decoding schedule and the log-likelihood updating formulae. The (check nodes) grouping method and decoding schedule optimize certain design criterion. The new normalized min-sum updating formula with a self-adjustable correction (scaling) factor offers better nonlinear approximation. Numerical performance of new GHSBP algorithms that include part or all three new techniques indicate that the combination of the proposed grouping and decoding schedule yields a faster convergence rate and our modified min-sum algorithm gives performance superior to that of the conventional min-sum and normalized min-sum algorithm and is very close to that of the sum-product algorithm.

IEEE International Symposium on Information Theory (ISIT)•Jun 1, 2009•4 citations

Combined Horizontal-Vertical Serial BP Decoding of GLDPC Codes with Binary Cyclic Codes

Kyuhyuk Chung

It is well known that serial belief propagation (BP) decoding for low-density parity-check (LDPC) codes achieves faster convergence without any increase of decoding complexity per iteration and bit error rate (BER) performance loss than standard parallel BP (PBP) decoding. Serial BP (SBP) decoding, such as horizontal SBP (H-SBP) decoding or vertical SBP (V-SBP) decoding, updates check nodes or variable nodes faster than standard PBP decoding within a single iteration. In this paper, we propose combined horizontal-vertical SBP (CHV-SBP) decoding. By the same reasoning, CHV-SBP decoding updates check nodes or variable nodes faster than SBP decoding within a serialized step in an iteration. CHV-SBP decoding achieves faster convergence than H-SBP or V-SBP decoding. We compare these decoding schemes in details. We also show in simulations that the convergence rate, in iterations, for CHV-SBP decoding is about $\frac{1}{6}$ of that for standard PBP decoding, while the convergence rate for SBP decoding is about $\frac{1}{2}$ of that for standard PBP decoding. In simulations, we use recently proposed generalized LDPC (GLDPC) codes with binary cyclic codes (BCC).

한국통신학회논문지•Oct 31, 2014•0 citations

A new optimization of group shuffled LDPC decoding

Nassib Laouini, Larbi Ben Hadj Slama, Ammar Bouallègue

Shuffled decoding is known to provide efficient and high-throughput implementation of LDPC decoders. In this paper, a new grouping technique of variable nodes to accelerate the message-passing rate is presented. In this algorithm, unlike other group-shuffled decoding methods, we consider for the first sub-group a set of variable nodes that has a low value of the intrinsic information, where the variable nodes of the code graph are divided into sub-groups called layers to perform group-by-group message-passing decoding and each iteration is broken into multiple sub-iterations. This paper proposes a simplification of the Variable Node group-shuffled Belief Propagation (Optimized VN group-shuffled BP) to lower the complexity of the check node update rule. Simulation results, verify that the Optimized VN group-shuffled BP does yield a faster convergence rate than both Belief Propagation (BP) and Check Node group-shuffled Belief Propagation (CN group-shuffled BP) decoder.

International Conference on Communications and Networking (ComNet)•Mar 1, 2014•0 citations

A Method for Grouping Symbol Nodes of Group Shuffled BP Decoding Algorithm

Y. Sato, Gou Hosoya, Hideki Yagi +1 more

In this paper, we propose a method for enhancing performance of a sequential version of the belief-propagation (BP) decoding algorithm, the group shuffled BP decoding algorithm for low-density parity-check (LDPC) codes. An improved BP decoding algorithm, called the shuffled BP decoding algorithm, decodes each symbol node in serial at each iteration. To reduce the decoding delay of the shuffled BP decoding algorithm, the group shuffled BP decoding algorithm divides all symbol nodes into several groups. In contrast to the original group shuffled BP, which automatically generates groups according to symbol positions, in this paper we propose a method for grouping symbol nodes which generates groups according to the structure of a Tanner graph of the codes. The proposed method can accelerate the convergence of the group shuffled BP algorithm and obtain a lower error rate in a small number of iterations. We show by simulation results that the decoding performance of the proposed method is improved compared with those of the shuffled BP decoding algorithm and the group shuffled BP decoding algorithm.

IEICE Transactions on Fundamentals of Electronics Communications and Computer Sciences•Oct 1, 2008•1 citation

A Group Shuffled BP decoding for punctured Low-Density Parity-Check codes

Sangjoon Park, Sunyoung Lee, Seung‐Hoon Hwang +1 more

A group shuffled belief propagation (GSBP) decoding for punctured low-density parity-check (LDPC) codes is proposed in the paper. The proposed GSBP decoding schedules the updating order of each bit node according to its recovery order in the standard BP decoding. This enables the proposed decoding to recover all punctured nodes in the first iteration with the minimum required number of groups. Calculation of the number of effective updates, which indicates the number of nonzero check-to-bit messages, shows that the proposed decoding can achieve faster decoding convergence than the layered BP (LBP) decoding for rate-compatible punctured LDPC (RCP-LDPC) codes. In the simulation results, the maximum SNR gain of the proposed decoding over the LBP decoding is about 0.9dB at the FER of 10-4.

IEICE Electronics Express•Jan 1, 2010•1 citation

Fast convergence decoding scheme tor regular LDPC codes

Jaebum Kim, Nam-Sik Kim, Hyuncheol Park

We propose a new belief propagation (BP) decoding algorithm for fast convergence decoding of regular LDPC codes. The fast convergence is achieved by grouping and scheduling updates of nodes on a bipartite-graph without additional computations or approximations. For this reason, the proposed algorithm can be applied to a serially constructed decoder, and can reduce the power consumption and decoding delay of the decoder. Simulation results show that the convergence speed of the proposed algorithm depends on the degree, d/sub v/, of the variable-nodes of the bipartite-graph, and the average number of iterations of the decoder can be reduced to (d/sub v/-1)/d/sub v/ by using the proposed algorithm without performance degradation or additional computation.

International Symposium on Intelligent Signal Processing and Communication Systems (ISPACS)•Jun 15, 2005•1 citation
Shuffled-BP (SBP) decoding algorithm is a variable-node-based serial decoding algorithm, which converges faster than the original Belief-Propagation (BP) decoding algorithm. However, due to the semi-parallel processing, there is a decrease in terms of convergence speed and error performance. An Overlapped Shuffled-BP(OSBP) decoding algorithm is proposed to enhance further the performance of the Shuffled-BP algorithm. In this algorithm, more than one sub-decoders are used to execute simultaneously, every sub-decoder has different updating order from each other. Regarding each variable node, the most reliable messages are kept and used for the next iteration, thus a faster convergence can be provided. Both theoretical analysis and simulation results show that, compared with SBP algorithm, OSBP algorithm possesses a better error performance as well as a higher convergence speed and introduces no extra storage requirement. Moreover, the proposed algorithm is effective for both regular and irregular LDPC codes.
Implementing a belief propagation (BP) based LDPC decoder requires high degrees of parallelism using many component soft-in soft-output (SISO) decoding units to perform message passing from variable nodes to check nodes or vice versa. An obvious complexity-reduction solution is to serialize the decoding process, i.e., dividing a decoding iteration into several serial sub-iterations in which a sub-iteration performs only part of the complete parallel message-passing operation. The group horizontal shuffled BP (GHSBP) and vertical shuffled BP (GVSBP) algorithms respectively partition the check and variable nodes of the code graph into groups to perform group-by-group message-passing decoding. This paper proposes new techniques to improve three key elements of a GHSBP decoding algorithm, namely, the grouping method, the decoding schedule and the log-likelihood updating formulae. The (check nodes) grouping method and decoding schedule optimize certain design criterion. The new normalized min-sum updating formula with a self-adjustable correction (scaling) factor offers better nonlinear approximation. Numerical performance of new GHSBP algorithms that include part or all three new techniques indicate that the combination of the proposed grouping and decoding schedule yields a faster convergence rate and our modified min-sum algorithm gives performance superior to that of the conventional min-sum and normalized min-sum algorithm and is very close to that of the sum-product algorithm.
It is well known that serial belief propagation (BP) decoding for low-density parity-check (LDPC) codes achieves faster convergence without any increase of decoding complexity per iteration and bit error rate (BER) performance loss than standard parallel BP (PBP) decoding. Serial BP (SBP) decoding, such as horizontal SBP (H-SBP) decoding or vertical SBP (V-SBP) decoding, updates check nodes or variable nodes faster than standard PBP decoding within a single iteration. In this paper, we propose combined horizontal-vertical SBP (CHV-SBP) decoding. By the same reasoning, CHV-SBP decoding updates check nodes or variable nodes faster than SBP decoding within a serialized step in an iteration. CHV-SBP decoding achieves faster convergence than H-SBP or V-SBP decoding. We compare these decoding schemes in details. We also show in simulations that the convergence rate, in iterations, for CHV-SBP decoding is about 16\frac{1}{6}61​ of that for standard PBP decoding, while the convergence rate for SBP decoding is about 12\frac{1}{2}21​ of that for standard PBP decoding. In simulations, we use recently proposed generalized LDPC (GLDPC) codes with binary cyclic codes (BCC).
Shuffled decoding is known to provide efficient and high-throughput implementation of LDPC decoders. In this paper, a new grouping technique of variable nodes to accelerate the message-passing rate is presented. In this algorithm, unlike other group-shuffled decoding methods, we consider for the first sub-group a set of variable nodes that has a low value of the intrinsic information, where the variable nodes of the code graph are divided into sub-groups called layers to perform group-by-group message-passing decoding and each iteration is broken into multiple sub-iterations. This paper proposes a simplification of the Variable Node group-shuffled Belief Propagation (Optimized VN group-shuffled BP) to lower the complexity of the check node update rule. Simulation results, verify that the Optimized VN group-shuffled BP does yield a faster convergence rate than both Belief Propagation (BP) and Check Node group-shuffled Belief Propagation (CN group-shuffled BP) decoder.
In this paper, we propose a method for enhancing performance of a sequential version of the belief-propagation (BP) decoding algorithm, the group shuffled BP decoding algorithm for low-density parity-check (LDPC) codes. An improved BP decoding algorithm, called the shuffled BP decoding algorithm, decodes each symbol node in serial at each iteration. To reduce the decoding delay of the shuffled BP decoding algorithm, the group shuffled BP decoding algorithm divides all symbol nodes into several groups. In contrast to the original group shuffled BP, which automatically generates groups according to symbol positions, in this paper we propose a method for grouping symbol nodes which generates groups according to the structure of a Tanner graph of the codes. The proposed method can accelerate the convergence of the group shuffled BP algorithm and obtain a lower error rate in a small number of iterations. We show by simulation results that the decoding performance of the proposed method is improved compared with those of the shuffled BP decoding algorithm and the group shuffled BP decoding algorithm.
A group shuffled belief propagation (GSBP) decoding for punctured low-density parity-check (LDPC) codes is proposed in the paper. The proposed GSBP decoding schedules the updating order of each bit node according to its recovery order in the standard BP decoding. This enables the proposed decoding to recover all punctured nodes in the first iteration with the minimum required number of groups. Calculation of the number of effective updates, which indicates the number of nonzero check-to-bit messages, shows that the proposed decoding can achieve faster decoding convergence than the layered BP (LBP) decoding for rate-compatible punctured LDPC (RCP-LDPC) codes. In the simulation results, the maximum SNR gain of the proposed decoding over the LBP decoding is about 0.9dB at the FER of 10-4.
We propose a new belief propagation (BP) decoding algorithm for fast convergence decoding of regular LDPC codes. The fast convergence is achieved by grouping and scheduling updates of nodes on a bipartite-graph without additional computations or approximations. For this reason, the proposed algorithm can be applied to a serially constructed decoder, and can reduce the power consumption and decoding delay of the decoder. Simulation results show that the convergence speed of the proposed algorithm depends on the degree, d/sub v/, of the variable-nodes of the bipartite-graph, and the average number of iterations of the decoder can be reduced to (d/sub v/-1)/d/sub v/ by using the proposed algorithm without performance degradation or additional computation.