Abstract

Low complexity decoding algorithms are necessary to meet data rate requirements in excess of 1 Tbps. In this paper, we study one and two bit message passing algorithms for belief propagation decoding of low-density parity-check (LDPC) codes and analyze them by density evolution. The variable nodes (VNs) exploit soft information from the channel output. To decrease the data flow, the messages exchanged between check nodes (CNs) and VNs are represented by one or two bits. The newly proposed quaternary message passing (QMP) algorithm is compared asymptotically and in finite length simulations to binary message passing (BMP) and ternary message passing (TMP) for spectrally efficient communication with higher-order modulation and probabilistic amplitude shaping (PAS). To showcase the potential for high throughput forward error correction, spatially coupled LDPC codes and a target spectral efficiency (SE) of 3 bits/QAM symbol are considered. Gains of about 0.7 dB and 0.1 dB are observed compared to BMP and TMP, respectively. The gap to unquantized belief propagation (BP) decoding is reduced to about 0.75 dB. For smaller code rates, the gain of QMP compared to TMP is more pronounced and amounts to 0.24 dB in the considered example.

© 2019 IEEE

Joint message passing decoding for LDPC codes with CCDMs

Yanan Luo and Qin Huang
Opt. Lett. 48(19) 4933-4936 (2023)

Improving soft FEC performance for higher-order modulations via optimized bit channel mappings

Christian Häger, Alexandre Graell i Amat, Fredrik Brännström, Alex Alvarado, and Erik Agrell
Opt. Express 22(12) 14544-14558 (2014)

Low-complexity LDPC decoding algorithms for ultra-high-order modulated signals

Hongjun Zhu, Meiyu Fu, Chen Hou, and Guijun Hu
Opt. Express 31(25) 41645-41657 (2023)

Fast phase error correction with reference beam-assisted LDPC coding for collinear holographic data storage

Qin Yu, Fei Wu, Meng Zhang, and Changsheng Xie
Opt. Express 31(12) 20345-20363 (2023)

Rate-Adaptive Modulation and Low-Density Parity-Check Coding for Optical Fiber Transmission Systems

Gwang-Hyun Gho and Joseph M. Kahn
J. Opt. Commun. Netw. 4(10) 760-768 (2012)