{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T13:36:23Z","timestamp":1785418583319,"version":"3.56.0"},"reference-count":33,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T00:00:00Z","timestamp":1776297600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["62301272"],"award-info":[{"award-number":["62301272"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["62301272"],"award-info":[{"award-number":["62301272"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Natural Science Research Start-up Foundation of Recruiting Talents of Nanjing University of Posts and Telecommunications under Grant","award":["NY223023"],"award-info":[{"award-number":["NY223023"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>To meet the future demands of high-rate transmission and full-coverage networks, radio frequency\u2013underwater wireless optical communication (RF-UWOC) relaying systems are considered a promising heterogeneous communication architecture. The rate-splitting (RS) scheme, through its power allocation (PA) mechanism, provides a generalized framework for the performance evaluation of such systems. Based on this, this paper analyzes the performance of an RS-based RF-UWOC system under hardware impairments (HIs) and interference. Analytical expressions of the outage probability (OP) and ergodic capacity (EC) for the considered system are formulated within a generalized framework, which encompasses the conventional RF-UWOC system as a special case. The results indicate that the OP and EC are affected by HIs, interference transmit power, the PA coefficients, channel fading, pointing errors (PEs), and detection types of the UWOC link. Furthermore, the asymptotic results for the OP and the diversity gain (DG) are explicitly characterized. For a fixed interference transmit power, the DG is mainly dominated by the channel fading severity, PEs effect, and the detection scheme. When the interference transmit power is comparable to the desired signal power, the system operates in an interference-limited regime, and the DG decreases to zero. It is also revealed that HIs and PA coefficients affect the coding gain but not the DG. Moreover, the existence of an optimal PA scheme improves the reliability of the RS-based system.<\/jats:p>","DOI":"10.3390\/e28040458","type":"journal-article","created":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T14:05:36Z","timestamp":1776348336000},"page":"458","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Rate-Splitting-Based RF-UWOC Relaying Systems with Hardware Impairments and Interference"],"prefix":"10.3390","volume":"28","author":[{"given":"Xin","family":"Huang","sequence":"first","affiliation":[{"name":"GAC Platform Technology Research Institute, Guangzhou Automobile Group Co., Ltd., Guangzhou 511434, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yeqing","family":"Su","sequence":"additional","affiliation":[{"name":"GAC Platform Technology Research Institute, Guangzhou Automobile Group Co., Ltd., Guangzhou 511434, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuehao","family":"Qiu","sequence":"additional","affiliation":[{"name":"School of Cyber Science and Engineering, Southeast University, Nanjing 211102, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xusheng","family":"Tang","sequence":"additional","affiliation":[{"name":"School of Cyber Science and Engineering, Southeast University, Nanjing 211102, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sai","family":"Li","sequence":"additional","affiliation":[{"name":"School of Communications and Information Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210003, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"13441","DOI":"10.1109\/TCOMM.2025.3600206","article-title":"Unified design of space-air-ground-sea integrated maritime communications","volume":"73","author":"Zhou","year":"2025","journal-title":"IEEE Trans. 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