{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,28]],"date-time":"2025-10-28T18:46:32Z","timestamp":1761677192145,"version":"build-2065373602"},"reference-count":22,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,5,26]],"date-time":"2023-05-26T00:00:00Z","timestamp":1685059200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Higher Education of Malaysia (MOHE)","award":["LRGS\/1\/2020\/UM\/01\/5\/4 (9012-00010)"],"award-info":[{"award-number":["LRGS\/1\/2020\/UM\/01\/5\/4 (9012-00010)"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>In this paper, we investigate the performance of spectral amplitude coding optical code division multiple access (SAC OCDMA) systems under the effect of beat noise and turbulence. Three different multi-laser source configurations are considered in this analysis: shared multi-laser, separate multi-laser, and carefully controlled center frequency separate multi-laser. We demonstrate through Monte Carlo simulation that the gamma\u2013gamma probability density function (pdf) cannot adequately approximate the measured intensity of overlapping lasers and that an empirical pdf is required. Results also show it is possible to achieve error-free transmission at a symmetrical data rate of 10 Gbps for all active users when only beat noise is taken into account by precisely controlling the center frequencies. However, only 30% of the active users can be supported when both beat noise and turbulence are considered.<\/jats:p>","DOI":"10.3390\/sym15061152","type":"journal-article","created":{"date-parts":[[2023,5,26]],"date-time":"2023-05-26T01:52:43Z","timestamp":1685065963000},"page":"1152","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Performance Analysis of Coherent Source SAC OCDMA in Free Space Optical Communication Systems"],"prefix":"10.3390","volume":"15","author":[{"given":"Ahmed M.","family":"Alhassan","sequence":"first","affiliation":[{"name":"Faculty of Engineering, Al Neelain University, Khartoum 11121, Sudan"},{"name":"Telecommunication Engineering Department, Mashreq University, Khartoum North 13317, Sudan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eithar","family":"Issam","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, Al Neelain University, Khartoum 11121, Sudan"}],"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 and Technology, Universiti Malaysia Perlis, Arau 02600, Perlis, Malaysia"},{"name":"Centre of Excellence Advanced Communication Engineering (ACE), Universiti Malaysia Perlis, Arau 02600, Perlis, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mohd Rashidi Che","family":"Beson","sequence":"additional","affiliation":[{"name":"Faculty of Electronic Engineering and Technology, Universiti Malaysia Perlis, Arau 02600, Perlis, Malaysia"},{"name":"Centre of Excellence Advanced Communication Engineering (ACE), Universiti Malaysia Perlis, Arau 02600, Perlis, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3630-2583","authenticated-orcid":false,"given":"Syed Mohammad","family":"Ammar","sequence":"additional","affiliation":[{"name":"Faculty of Electronic Engineering and Technology, Universiti Malaysia Perlis, Arau 02600, Perlis, Malaysia"},{"name":"Centre of Excellence Advanced Communication Engineering (ACE), Universiti Malaysia Perlis, Arau 02600, Perlis, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9348-0714","authenticated-orcid":false,"given":"Norshamsuri","family":"Ali","sequence":"additional","affiliation":[{"name":"Faculty of Electronic Engineering and Technology, Universiti Malaysia Perlis, Arau 02600, Perlis, Malaysia"},{"name":"Centre of Excellence Advanced Communication Engineering (ACE), Universiti Malaysia Perlis, Arau 02600, Perlis, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3659-9740","authenticated-orcid":false,"given":"Rosdisham","family":"Endut","sequence":"additional","affiliation":[{"name":"Faculty of Electronic Engineering and Technology, Universiti Malaysia Perlis, Arau 02600, Perlis, Malaysia"},{"name":"Centre of Excellence Advanced Communication Engineering (ACE), Universiti Malaysia Perlis, Arau 02600, Perlis, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"307","DOI":"10.1364\/JOCN.1.000307","article-title":"Circle Polarization Shift Keying With Direct Detection for Free-Space Optical Communication","volume":"1","author":"Zhao","year":"2009","journal-title":"IEEE\/OSA J. 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