Architecture design of QC-LDPC decoder with cyclicly-coupled codes

In this paper, we propose a new class of quasi-cyclic low-density parity-check (QC-LDPC) codes, namely cyclically-coupled QC-LDPC (CC-QC-LDPC) codes, and their RAM-based decoder architecture. CC-QC-LDPC codes have a simple structure and are constructed by cyclically-coupling a number of QC-LDPC subcodes. They can achieve throughput and error performance as excellent as LDPC convolutional codes, but with much lower hardware requirements. They are therefore promising candidates for future generations of communication systems such as long-haul optical communication systems. In particular, a rate-5/6 CC-QC-LDPC decoder has been implemented onto a field-programmable gate array (FPGA) and it achieves a throughput of 3.0 Gb/s at 100 MHz clock rate with 10-iteration decoding. No error floor is observed up to an $E_{b}/N_{0}$ of 3.50 dB, where all $1.14\times 10^{16}$ transmitted bits have been decoded correctly.In this paper, we propose a new class of quasi-cyclic low-density parity-check (QC-LDPC) codes, namely cyclically-coupled QC-LDPC (CC-QC-LDPC) codes, and their RAM-based decoder architecture. CC-QC-LDPC codes have a simple structure and are constructed by cyclically-coupling a number of QC-LDPC subcodes. They can achieve throughput and error performance as excellent as LDPC convolutional codes, but with much lower hardware requirements. They are therefore promising candidates for future generations of communication systems such as long-haul optical communication systems. In particular, a rate-5/6 CC-QC-LDPC decoder has been implemented onto a field-programmable gate array (FPGA) and it achieves a throughput of 3.0 Gb/s at 100 MHz clock rate with 10-iteration decoding. No error floor is observed up to an$E_{b}/N_{0}$of 3.50 dB, where all$1.14\times 10^{16}$transmitted bits have been decoded correctly.

IEEE Transactions on Circuits and Systems I Regular PapersJan 1, 201634 citations

Implementation of Cyclic-Layered QC-LDPC decoder on FPGA

Jianfeng Fan

Jan 1, 20130 citations

Efficient column-layered decoders for single block-row quasi-cyclic LDPC codes

Chuan Zhang, Xiaohu You, Zhongfeng Wang

The recently proposed single block-row quasi-cyclic low-density parity-check (QC-LDPC) codes are favorable for high-speed applications. However, conventional decoder design methods are not suitable for this kind of codes. To tackle this issue, this paper aims at designing efficient column-layered single block-row QC-LDPC decoder architecture without affecting the decoding performance. Moreover, the simplified version which only requires single minimum value is also proposed for further hardware reduction. Results show that, for the rate-0.9006 (1640, 1477) single block-row QC-LDPC code, the proposed two designs achieves significant advantages in both hardware and latency over their row-layered counterpart.The recently proposed single block-row quasi-cyclic low-density parity-check (QC-LDPC) codes are favorable for high-speed applications. However, conventional decoder design methods are not suitable for this kind of codes. To tackle this issue, this paper aims at designing efficient column-layered single block-row QC-LDPC decoder architecture without affecting the decoding performance. Moreover, the simplified version which only requires single minimum value is also proposed for further hardware reduction. Results show that, for the rate-0.9006 (1640, 1477) single block-row QC-LDPC code, the proposed two designs achieves significant advantages in both hardware and latency over their row-layered counterpart.

IEEE International Symposium on Circuits and Systems proceedingsJun 1, 20142 citations

Design of QC-LDPC Codes at Finite Lengths

Hyunki Kim, Eugene Ha, Jeongseok Ha

Sep 9, 20260 citations

A flexible and overlapped QC-LDPC decoder

Gabofetswe Malema

There are many low-density parity-check (LDPC) decoder architectures in the literature most of which are based on structured codes. Besides been specific to a particular class of codes, suggested architectures are limited in scalability. The major challenge in decoder design and implementation is the consideration of several strongly interrelated factors. These factors affect decoder computation and communication complexity, and error-correcting performance. In this paper we present a low-complexity, flexible and scalable LDPC decoder architecture for quasi-cyclic codes that supports multiple code designs (size, weights, rates, regular and irregular). The architecture is a result of a combination of flexible code construction and computation overlapping techniques. The architecture is based on overlapping techniques that allow sequential processing of check and variable nodes. The overlapping techniques lead to a low-complexity decoder interconnect compared to the existing techniques as they allow serial processing of code sub-matrices as compared to parallel processing of all sub-matrices in the existing overlapping technique. Although the architecture is based on quasi-cyclic codes, it can also be applied to random or other structured codes making it the most flexible, scalable and high-throughput partly-parallel LDPC decoder architecture.There are many low-density parity-check (LDPC) decoder architectures in the literature most of which are based on structured codes. Besides been specific to a particular class of codes, suggested architectures are limited in scalability. The major challenge in decoder design and implementation is the consideration of several strongly interrelated factors. These factors affect decoder computation and communication complexity, and error-correcting performance. In this paper we present a low-complexity, flexible and scalable LDPC decoder architecture for quasi-cyclic codes that supports multiple code designs (size, weights, rates, regular and irregular). The architecture is a result of a combination of flexible code construction and computation overlapping techniques. The architecture is based on overlapping techniques that allow sequential processing of check and variable nodes. The overlapping techniques lead to a low-complexity decoder interconnect compared to the existing techniques as they allow serial processing of code sub-matrices as compared to parallel processing of all sub-matrices in the existing overlapping technique. Although the architecture is based on quasi-cyclic codes, it can also be applied to random or other structured codes making it the most flexible, scalable and high-throughput partly-parallel LDPC decoder architecture.

Oct 1, 20081 citation

Design and FPGA Implementation of a Quasi-Cyclic LDPC Decoder

Honglin Zhao, Haiyue Zhang

Lecture notes in electrical engineeringJun 6, 20181 citation

E_{b}/N_{0}

of 3.50 dB, where all

1.14\times 10^{16}

transmitted bits have been decoded correctly.