TY - JOUR
T1 - Design and Optimization of Protograph LDPC-Coded Multipulse PPM Systems over Poisson Channels
AU - Yang, Zhaojie
AU - Fang, Yi
AU - Zhang, Guohua
AU - Lau, Francis C.M.
N1 - This work was supported in part by the NSF of China under Grant 62071131, the RGC Research Impact Fund from the Hong Kong SAR, China (Project No. R5013-19), the Guangdong Basic and Applied Basic Research Foundation under Grant 2022B1515020086, and the NSF of Guangdong Province under Grant 2019A1515011465. The associate editor coordinating the review of this article and
approving it for publication was H. Nguyen.
Publisher Copyright:
IEEE
PY - 2022/6
Y1 - 2022/6
N2 - Combining powerful error-correction codes (ECCs) with multipulse pulse-position modulation (MPPM) has great potential to realize high-throughput and high-reliability transmissions in free-space optical (FSO) communication systems. This paper conducts an insightful investigation on protograph low-density parity-check (PLDPC)-coded MPPM systems over Poisson channels. To be specific, we first put forward a novel type of constellations, referred to as irregular pulse-distribution (IPD) constellations, for MPPM. We also conceive a bit-level rate-adaptive (RA) scheme, which can exploit the structural property of the IPD constellations to significantly improve the convergence performance at the price of transmission-rate loss. Furthermore, with the aid of a modified protograph extrinsic information transfer (PEXIT) algorithm, we construct three enhanced PLDPC codes with code rates 1/2, 2/3 and 3/4 that exhibit excellent decoding thresholds over Poisson channels. The proposed PLDPC-coded MPPM systems with the use of the IPD constellations, RA scheme, and enhanced PLDPC codes are superior to the state-of-the-art counterparts.
AB - Combining powerful error-correction codes (ECCs) with multipulse pulse-position modulation (MPPM) has great potential to realize high-throughput and high-reliability transmissions in free-space optical (FSO) communication systems. This paper conducts an insightful investigation on protograph low-density parity-check (PLDPC)-coded MPPM systems over Poisson channels. To be specific, we first put forward a novel type of constellations, referred to as irregular pulse-distribution (IPD) constellations, for MPPM. We also conceive a bit-level rate-adaptive (RA) scheme, which can exploit the structural property of the IPD constellations to significantly improve the convergence performance at the price of transmission-rate loss. Furthermore, with the aid of a modified protograph extrinsic information transfer (PEXIT) algorithm, we construct three enhanced PLDPC codes with code rates 1/2, 2/3 and 3/4 that exhibit excellent decoding thresholds over Poisson channels. The proposed PLDPC-coded MPPM systems with the use of the IPD constellations, RA scheme, and enhanced PLDPC codes are superior to the state-of-the-art counterparts.
KW - Codes
KW - Decoding
KW - Design methodology
KW - free-space optical communication
KW - multipulse pulse-position modulation
KW - Optical receivers
KW - Optical sensors
KW - Optimization
KW - Poisson channel
KW - protograph low-density parity-check
KW - Symbols
UR - http://www.scopus.com/inward/record.url?scp=85131757956&partnerID=8YFLogxK
U2 - 10.1109/TVT.2022.3179483
DO - 10.1109/TVT.2022.3179483
M3 - Journal article
AN - SCOPUS:85131757956
SP - 1
EP - 16
JO - IEEE Transactions on Vehicular Communications
JF - IEEE Transactions on Vehicular Communications
SN - 0018-9545
M1 - 9786657
ER -