{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:43:37Z","timestamp":1760060617143,"version":"build-2065373602"},"reference-count":25,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,9,4]],"date-time":"2025-09-04T00:00:00Z","timestamp":1756944000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key Research and Development Program","award":["2022YFC3005702","62371101","62461017","IA20240000001","2023KP01609","2022GXNSFBA035508","2023GXNSFAA026018"],"award-info":[{"award-number":["2022YFC3005702","62371101","62461017","IA20240000001","2023KP01609","2022GXNSFBA035508","2023GXNSFAA026018"]}]},{"name":"National Natural Science Foundation of China","award":["2022YFC3005702","62371101","62461017","IA20240000001","2023KP01609","2022GXNSFBA035508","2023GXNSFAA026018"],"award-info":[{"award-number":["2022YFC3005702","62371101","62461017","IA20240000001","2023KP01609","2022GXNSFBA035508","2023GXNSFAA026018"]}]},{"name":"ZTE Industry-University-Institute Cooperation Funds","award":["2022YFC3005702","62371101","62461017","IA20240000001","2023KP01609","2022GXNSFBA035508","2023GXNSFAA026018"],"award-info":[{"award-number":["2022YFC3005702","62371101","62461017","IA20240000001","2023KP01609","2022GXNSFBA035508","2023GXNSFAA026018"]}]},{"name":"National Key Laboratory of Wireless Communications Foundation","award":["2022YFC3005702","62371101","62461017","IA20240000001","2023KP01609","2022GXNSFBA035508","2023GXNSFAA026018"],"award-info":[{"award-number":["2022YFC3005702","62371101","62461017","IA20240000001","2023KP01609","2022GXNSFBA035508","2023GXNSFAA026018"]}]},{"name":"Natural Science Foundation of Guangxi","award":["2022YFC3005702","62371101","62461017","IA20240000001","2023KP01609","2022GXNSFBA035508","2023GXNSFAA026018"],"award-info":[{"award-number":["2022YFC3005702","62371101","62461017","IA20240000001","2023KP01609","2022GXNSFBA035508","2023GXNSFAA026018"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>In this paper, some optimized encoding and decoding schemes are proposed for the generalized LDPC convolutional codes (GLDPC\u2013CCs). In terms of the encoding scheme, a flexible doping method is proposed, which replaces multiple single parity check (SPC) nodes with one generalized check (GC) node. Different types of BCH codes can be selected as the GC node by adjusting the number of SPC nodes to be replaced. Moreover, by fine-tuning the truncated bits and the extended parity check bits, or by reasonably adjusting the GC node distribution, the performance of GLDPC\u2013CCs can be further improved. In terms of the decoding scheme, a hybrid layered normalized min-sum (HLNMS) decoding algorithm is proposed, where the layered normalized min-sum (LNMS) decoding is used for SPC nodes, and the Chase\u2013Pyndiah decoding is adopted for GC nodes. Based on analysis of the decoding convergence of GC node and SPC node, an adaptive weight factor is designed for GC nodes that changes as the decoding iterations, aiming to further improve the decoding performance. In addition, an early stop decoding strategy is also proposed based on the minimum amplitude threshold of mutual information in order to reduce the decoding complexity. The simulation results have verified the superiority of the proposed scheme for GLDPC\u2013CCs over the prior art, which has great application potential in optical communication systems.<\/jats:p>","DOI":"10.3390\/e27090930","type":"journal-article","created":{"date-parts":[[2025,9,4]],"date-time":"2025-09-04T09:18:57Z","timestamp":1756977537000},"page":"930","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Optimized Generalized LDPC Convolutional Codes"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9478-551X","authenticated-orcid":false,"given":"Li","family":"Deng","sequence":"first","affiliation":[{"name":"Yangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China, Huzhou 313000, China"},{"name":"National Key Laboratory on Communications, University of Electronic Science and Technology of China, Chengdu 611731, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kai","family":"Tao","sequence":"additional","affiliation":[{"name":"ZTE Corporation, Shenzhen 518057, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhiping","family":"Shi","sequence":"additional","affiliation":[{"name":"Yangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China, Huzhou 313000, China"},{"name":"National Key Laboratory on Communications, University of Electronic Science and Technology of China, Chengdu 611731, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"You","family":"Zhang","sequence":"additional","affiliation":[{"name":"National Key Laboratory on Communications, University of Electronic Science and Technology of China, Chengdu 611731, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yinlong","family":"Shi","sequence":"additional","affiliation":[{"name":"ZTE Corporation, Shenzhen 518057, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jian","family":"Wang","sequence":"additional","affiliation":[{"name":"ZTE Corporation, Shenzhen 518057, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tian","family":"Liu","sequence":"additional","affiliation":[{"name":"ZTE Corporation, Shenzhen 518057, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yongben","family":"Wang","sequence":"additional","affiliation":[{"name":"ZTE Corporation, Shenzhen 518057, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"533","DOI":"10.1109\/TIT.1981.1056404","article-title":"A recursive approach to low complexity codes","volume":"27","author":"Tanner","year":"1981","journal-title":"IEEE Trans. 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