{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,7]],"date-time":"2026-02-07T12:07:59Z","timestamp":1770466079725,"version":"3.49.0"},"reference-count":44,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2023,7,30]],"date-time":"2023-07-30T00:00:00Z","timestamp":1690675200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Key Program of Marine Economy Development Special Foundation of Department of Natural Resources of Guangdong Province","award":["GDNRC [2023]24"],"award-info":[{"award-number":["GDNRC [2023]24"]}]},{"name":"Key Program of Marine Economy Development Special Foundation of Department of Natural Resources of Guangdong Province","award":["220202"],"award-info":[{"award-number":["220202"]}]},{"name":"Key Program of Marine Economy Development Special Foundation of Department of Natural Resources of Guangdong Province","award":["62271426"],"award-info":[{"award-number":["62271426"]}]},{"name":"Key Program of Marine Economy Development Special Foundation of Department of Natural Resources of Guangdong Province","award":["KY-080000-04-2022-025"],"award-info":[{"award-number":["KY-080000-04-2022-025"]}]},{"name":"Key Laboratory of Southeast Coast Marine Information Intelligent Perception and Application, MNR","award":["GDNRC [2023]24"],"award-info":[{"award-number":["GDNRC [2023]24"]}]},{"name":"Key Laboratory of Southeast Coast Marine Information Intelligent Perception and Application, MNR","award":["220202"],"award-info":[{"award-number":["220202"]}]},{"name":"Key Laboratory of Southeast Coast Marine Information Intelligent Perception and Application, MNR","award":["62271426"],"award-info":[{"award-number":["62271426"]}]},{"name":"Key Laboratory of Southeast Coast Marine Information Intelligent Perception and Application, MNR","award":["KY-080000-04-2022-025"],"award-info":[{"award-number":["KY-080000-04-2022-025"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China (NSFC)","doi-asserted-by":"publisher","award":["GDNRC [2023]24"],"award-info":[{"award-number":["GDNRC [2023]24"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China (NSFC)","doi-asserted-by":"publisher","award":["220202"],"award-info":[{"award-number":["220202"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China (NSFC)","doi-asserted-by":"publisher","award":["62271426"],"award-info":[{"award-number":["62271426"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China (NSFC)","doi-asserted-by":"publisher","award":["KY-080000-04-2022-025"],"award-info":[{"award-number":["KY-080000-04-2022-025"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Natural Resources Science and Technology Innovation Project Of Fujian","award":["GDNRC [2023]24"],"award-info":[{"award-number":["GDNRC [2023]24"]}]},{"name":"Natural Resources Science and Technology Innovation Project Of Fujian","award":["220202"],"award-info":[{"award-number":["220202"]}]},{"name":"Natural Resources Science and Technology Innovation Project Of Fujian","award":["62271426"],"award-info":[{"award-number":["62271426"]}]},{"name":"Natural Resources Science and Technology Innovation Project Of Fujian","award":["KY-080000-04-2022-025"],"award-info":[{"award-number":["KY-080000-04-2022-025"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The performance of the underwater acoustic (UWA) orthogonal frequency division multiplexing (OFDM) system is often restrained by time-varying channels with large delays. The existing frequency domain equalizers do not work well because of the high complexity and difficulty of finding the real-time signal-to-noise ratio. To solve these problems, we propose a low-complexity neural network (NN)-based scheme for joint equalization and detection. A simple NN structure is built to yield the detected symbols with the joint input of the segmented channel response and received symbol. The coherence bandwidth is investigated to find the optimal hyperparameters. By being completely trained offline with real channels, the proposed detector is applied independently in both simulations and sea trials. The results show that the proposed detector outperforms the ZF and MMSE equalizers and extreme learning machine (ELM)-based detectors in both the strongly reflected channels of the pool and time-variant channels of the shallow sea. The complexity of the proposed network is lower than the MMSE and ELM-based receiver.<\/jats:p>","DOI":"10.3390\/rs15153796","type":"journal-article","created":{"date-parts":[[2023,7,31]],"date-time":"2023-07-31T01:48:50Z","timestamp":1690768130000},"page":"3796","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Neural-Network-Based Equalization and Detection for Underwater Acoustic Orthogonal Frequency Division Multiplexing Communications: A Low-Complexity Approach"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2799-8491","authenticated-orcid":false,"given":"Mingzhang","family":"Zhou","sequence":"first","affiliation":[{"name":"School of Informatics, Xiamen University, Xiamen 361005, China"},{"name":"Key Laboratory of Southeast Coast Marine Information Intelligent Perception and Application, Ministry of Natural Resources, Zhangzhou 363000, China"}]},{"given":"Junfeng","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Southeast Coast Marine Information Intelligent Perception and Application, Ministry of Natural Resources, Zhangzhou 363000, China"},{"name":"School of Integrated Circuit Science and Engineering, Tianjin University of Technology, Tianjin 300384, China"}]},{"given":"Xiao","family":"Feng","sequence":"additional","affiliation":[{"name":"Key Laboratory of Broadband Wireless Communication and Sensor Network Technology, Nanjing University of Posts and Telecommunications, Nanjing 210023, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8249-1197","authenticated-orcid":false,"given":"Haixin","family":"Sun","sequence":"additional","affiliation":[{"name":"School of Informatics, Xiamen University, Xiamen 361005, China"},{"name":"Key Laboratory of Southeast Coast Marine Information Intelligent Perception and Application, Ministry of Natural Resources, Zhangzhou 363000, China"}]},{"given":"Jie","family":"Qi","sequence":"additional","affiliation":[{"name":"School of Electornic Science and Engineering (National Model Microelectronics College), Xiamen University, Xiamen 361005, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6283-7186","authenticated-orcid":false,"given":"Rongbin","family":"Lin","sequence":"additional","affiliation":[{"name":"School of Informatics, Xiamen University, Xiamen 361005, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1502205","DOI":"10.1109\/LGRS.2023.3286180","article-title":"Multireceiver SAS Imagery with Generalized PCA","volume":"20","author":"Zhang","year":"2023","journal-title":"IEEE Geosci. 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