{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,13]],"date-time":"2025-11-13T07:25:38Z","timestamp":1763018738410,"version":"build-2065373602"},"reference-count":43,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,1,2]],"date-time":"2025-01-02T00:00:00Z","timestamp":1735776000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Research and Development of the ICT Priority Technology Project","award":["JPMI00316"],"award-info":[{"award-number":["JPMI00316"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Information"],"abstract":"<jats:p>This study proposes a novel optical wireless communication system for high-speed, large-capacity data transmission, supporting underwater IoT devices in shallow seas. The system employs a mirror-equipped aerial drone as a relay between underwater drones and a terrestrial station, using 850 nm optical signals for low atmospheric loss and enhanced confidentiality. Adaptive modulation optimizes transmission capacity based on SNR, accounting for air and underwater channel characteristics. Experiments confirmed an exponential SNR decrease with distance (0.6\u20131.8 m) and demonstrated successful 4K UHD video streaming in shallow seawater (turbidity: 2.2 NTU) without quality loss. The design ensures cost-effectiveness and stable optical alignment using advanced posture control.<\/jats:p>","DOI":"10.3390\/info16010019","type":"journal-article","created":{"date-parts":[[2025,1,2]],"date-time":"2025-01-02T06:05:10Z","timestamp":1735797910000},"page":"19","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Depth-Adaptive Air and Underwater Invisible Light Communication System with Aerial Reflection Repeater Assistance"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7857-3461","authenticated-orcid":false,"given":"Takahiro","family":"Kodama","sequence":"first","affiliation":[{"name":"Faculty of Engineering and Design, Kagawa University, 2217-20 Hayashi-cho, Takamatsu 761-0396, Kagawa, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Keita","family":"Tanaka","sequence":"additional","affiliation":[{"name":"LED Backhaul Project, Sangikyo Corporation, 4509 Ikebe-machi, Tsuzuki-ku, Yokohama-shi 224-0053, Kanagawa, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kiichiro","family":"Kuwahara","sequence":"additional","affiliation":[{"name":"Faculty of Engineering and Design, Kagawa University, 2217-20 Hayashi-cho, Takamatsu 761-0396, Kagawa, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ayumu","family":"Kariya","sequence":"additional","affiliation":[{"name":"Faculty of Engineering and Design, Kagawa University, 2217-20 Hayashi-cho, Takamatsu 761-0396, Kagawa, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shogo","family":"Hayashida","sequence":"additional","affiliation":[{"name":"LED Backhaul Project, Sangikyo Corporation, 4509 Ikebe-machi, Tsuzuki-ku, Yokohama-shi 224-0053, Kanagawa, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4297","DOI":"10.1109\/TII.2019.2946618","article-title":"Underwater Internet of Things in Smart Ocean: System Architecture and Open Issues","volume":"16","author":"Qiu","year":"2020","journal-title":"IEEE Trans. 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