{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T22:52:42Z","timestamp":1777503162106,"version":"3.51.4"},"reference-count":59,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,3,16]],"date-time":"2023-03-16T00:00:00Z","timestamp":1678924800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>In recent years, optical wireless communication has promised several benefits over radio frequency communication in atmospheric, deep space and underwater communications. Satellite-to-underwater communication technology can be applied to commercial, naval, scientific and engineering operations because of its high data rate, high security, long-reach and low cost. In this paper, a high-speed, long-reach integrated free space optics (FSO)-passive optical network (PON) system using non-orthogonal multiple access visible light communication (NOMA-VLC) is proposed. It poses a 10\/2.5 Gbps per channel bit rate for satellite-to-underwater applications. Numerically calculated results provide the splitter power budget of \u221235 dBm in the downlink and \u221232 dBm in the uplink. Additionally, a receiver sensitivity of 23 dB in the downlink and 10 dB in the uplink direction can be obtained in the system using a modified new zero cross-correlation (MNZCC) code under clear environment conditions. Again, the simulative analyses indicate that the suggested system supports 290 underwater devices successfully and offers a high 10 dBm signal-to-noise ratio over 10 km FSO, 100 km fiber and 5 m VLC range. Moreover, it provides a signal-to-noise ratio of 39 dB, with \u22129 dBm received optical power at 300 fields of view under fiber-wireless channels\u2019 impairments. We argue that the suggested system is a symmetric system adapted to different link distances and which offers improved receiver sensitivity and high received optical power at a 10\u22129 bit error rate (BER). The comparative analysis shows the advantages of the suggested system over previously reported works.<\/jats:p>","DOI":"10.3390\/sym15030739","type":"journal-article","created":{"date-parts":[[2023,3,17]],"date-time":"2023-03-17T04:10:48Z","timestamp":1679026248000},"page":"739","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Modeling of Satellite-to-Underwater Integrated FSO-PON System Using NOMA-VLC"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9749-4865","authenticated-orcid":false,"given":"Vivek","family":"Arya","sequence":"first","affiliation":[{"name":"Department of Electronics and Communication Engineering, FET, Gurukula Kangri (Deemed to be University), Haridwar 249404, Uttarakhand, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Meet","family":"Kumari","sequence":"additional","affiliation":[{"name":"Department of Electronics and Communication Engineering, Chandigarh University, Mohali 140413, Punjab, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3620-581X","authenticated-orcid":false,"given":"Hamza Mohammed Ridha","family":"Al-Khafaji","sequence":"additional","affiliation":[{"name":"Biomedical Engineering Department, Al-Mustaqbal University College, Hillah 51001, Babil, Iraq"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2739-6220","authenticated-orcid":false,"given":"Syed Alwee","family":"Aljunid","sequence":"additional","affiliation":[{"name":"Faculty of Electronic Engineering Technology, Universiti Malaysia Perlis, Arau 02600, Perlis, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"127141","DOI":"10.1016\/j.optcom.2021.127141","article-title":"Performance Analysis of Mixed FSO-RF Transmission in Multiuser Satellite\u2013Aerial\u2013Terrestrial Networks","volume":"496","author":"Liu","year":"2021","journal-title":"Opt. 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