Title
One and Two Bit Message Passing for SC-LDPC Codes with Higher-Order Modulation.
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.
Year
DOI
Venue
2019
10.1109/JLT.2019.2943324
Journal of Lightwave Technology
Keywords
DocType
Volume
Decoding,Message passing,Modulation,Gain,Iterative decoding,Probabilistic logic
Journal
37
Issue
ISSN
Citations 
23
0733-8724
0
PageRank 
References 
Authors
0.34
0
5
Name
Order
Citations
PageRank
Fabian Steiner16511.68
Emna Ben Yacoub201.01
Balázs Matuz300.34
Gianluigi Liva486175.40
Amat Alexandre Graell i545665.56