{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T19:35:18Z","timestamp":1780428918510,"version":"3.54.1"},"reference-count":41,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2020,1,11]],"date-time":"2020-01-11T00:00:00Z","timestamp":1578700800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>An important step in the design of receiver aperture and optimal spacing of the diversity scheme for an underwater laser communication system is to accurately characterize the two-dimensional (2D) spatial distribution of laser beam intensity. In this paper, the 2D optical intensity distribution and 3 dB optical intensity spot radius (OISR) are investigated due to the dominating optical intensity of laser beam being within the 3 dB OISR. By utilizing the Henyey\u2013Greenstein function to compute the scattering angles of photons, the effects of the scattering underwater optical channel and optical system parameters on 3 dB OISR are examined based on the Monte Carlo simulation method. We have shown for the first time that in the channel with a high density of scattering particles, the divergence angle of the laser source plays a negligible role in 3 dB OISR. This is an interesting phenomenon and important for optical communication as this clearly shows that the geometric loss is no longer important for the design of receiver aperture and optimal spacing of the diversity scheme for the underwater laser communication system in the highly scattering channel.<\/jats:p>","DOI":"10.3390\/s20020422","type":"journal-article","created":{"date-parts":[[2020,1,13]],"date-time":"2020-01-13T04:05:51Z","timestamp":1578888351000},"page":"422","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Investigation of 3 dB Optical Intensity Spot Radius of Laser Beam under Scattering Underwater Channel"],"prefix":"10.3390","volume":"20","author":[{"given":"Wei","family":"Wang","sequence":"first","affiliation":[{"name":"Ministry of Education Key Laboratory of Cognitive Radio and Information Processing, Guilin University of Electronic Technology, Guilin 541004, China"},{"name":"Guangxi Experiment Center of Information Science, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoji","family":"Li","sequence":"additional","affiliation":[{"name":"Ministry of Education Key Laboratory of Cognitive Radio and Information Processing, Guilin University of Electronic Technology, Guilin 541004, China"},{"name":"Guangxi Experiment Center of Information Science, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sujan","family":"Rajbhandari","sequence":"additional","affiliation":[{"name":"Institute of Future Transport and Cities, School of Computing, Electronics and Mathematics, Coventry University, Coventry CV15FB, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanlong","family":"Li","sequence":"additional","affiliation":[{"name":"Ministry of Education Key Laboratory of Cognitive Radio and Information Processing, Guilin University of Electronic Technology, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1518","DOI":"10.1109\/ACCESS.2016.2552538","article-title":"Underwater optical wireless communication","volume":"4","author":"Kaushal","year":"2016","journal-title":"IEEE Access"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1016\/j.optcom.2017.08.002","article-title":"Underwater optical communications using orbital angular momentum-based spatial divisionmultiplexing","volume":"19","author":"Willner","year":"2018","journal-title":"Opt. 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