{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T12:27:56Z","timestamp":1775219276588,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2023,9,3]],"date-time":"2023-09-03T00:00:00Z","timestamp":1693699200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Science Foundation of China","doi-asserted-by":"publisher","award":["62001333"],"award-info":[{"award-number":["62001333"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Science Foundation of China","doi-asserted-by":"publisher","award":["20220609"],"award-info":[{"award-number":["20220609"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Science Foundation of China","doi-asserted-by":"publisher","award":["2023AFB291"],"award-info":[{"award-number":["2023AFB291"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Incubation Project of Wuhan Textile University","award":["62001333"],"award-info":[{"award-number":["62001333"]}]},{"name":"National Incubation Project of Wuhan Textile University","award":["20220609"],"award-info":[{"award-number":["20220609"]}]},{"name":"National Incubation Project of Wuhan Textile University","award":["2023AFB291"],"award-info":[{"award-number":["2023AFB291"]}]},{"name":"2023 Hubei Provincial Natural Science Foundation","award":["62001333"],"award-info":[{"award-number":["62001333"]}]},{"name":"2023 Hubei Provincial Natural Science Foundation","award":["20220609"],"award-info":[{"award-number":["20220609"]}]},{"name":"2023 Hubei Provincial Natural Science Foundation","award":["2023AFB291"],"award-info":[{"award-number":["2023AFB291"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Nowadays, unmanned aerial vehicle (UAV) communication systems are commonly considered as one of the key enabling technologies for 6G. The hybrid free space optical (FSO)\/radio frequency (RF) system has the advantages of both FSO and RF links to improve communication system performance, and the relay-assisted system adopts multi-hop transmission and cooperative diversity methods to extend communication coverage. Thus, a joint consideration of UAV-assistedUAV assisted relay in hybrid FSO\/RF transmission is meaningful. In this paper, we aim to analyze the performance of UAV-assisted multi-hop parallel hybrid FSO\/RF communication systems with and without pointing errors (PE) in terms of Bit Error Rate (BER) and outage probability. In our considered system, the FSO sub-link adopts the Exponential Weibull turbulence model and the RF sub-link suffers the Nakagami fading model. With these, new mathematical formulas of both BER and outage probability are derived under the UAV-assisted hybrid FSO\/RF with different modulation methods. Through numerical evaluationnumerical simulations, the performances of UAV-assisted hybrid FSO\/RF systems are analyzed under different weather conditions, modulation methods, optical receiver aperture, RF fading parameters, pointing errors, and relay structures. The results demonstrate that (1) compared to hybrid FSO\/RF direct links, UAV-assisted hybrid FSO\/RF systems can further improve system performance; (2) the performance of UAV-assisted hybrid FSO\/RF systems varies with different relay structures; (3) large receiver aperture and RF fading parameters can further improve the communication performance of hybrid FSO\/RF direct links and UAV-assisted hybrid FSO\/RF systems.<\/jats:p>","DOI":"10.3390\/s23177638","type":"journal-article","created":{"date-parts":[[2023,9,4]],"date-time":"2023-09-04T02:59:55Z","timestamp":1693796395000},"page":"7638","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Performance Analysis of UAV-Assisted Hybrid FSO\/RF Communication Systems under Various Weather Conditions"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2878-8410","authenticated-orcid":false,"given":"Yan","family":"Wu","sequence":"first","affiliation":[{"name":"The State Key Laboratory of New Textile Materials and Advanced Processing Technologies, School of Electronic and Electrical Engineering, Wuhan Textile University, Wuhan 430200, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7119-9895","authenticated-orcid":false,"given":"Dejin","family":"Kong","sequence":"additional","affiliation":[{"name":"The State Key Laboratory of New Textile Materials and Advanced Processing Technologies, School of Electronic and Electrical Engineering, Wuhan Textile University, Wuhan 430200, China"}]},{"given":"Qian","family":"Wang","sequence":"additional","affiliation":[{"name":"The State Key Laboratory of New Textile Materials and Advanced Processing Technologies, School of Electronic and Electrical Engineering, Wuhan Textile University, Wuhan 430200, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4725-2753","authenticated-orcid":false,"given":"Gang","family":"Li","sequence":"additional","affiliation":[{"name":"The State Key Laboratory of New Textile Materials and Advanced Processing Technologies, School of Electronic and Electrical Engineering, Wuhan Textile University, Wuhan 430200, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2951","DOI":"10.1007\/s11277-021-08380-9","article-title":"Free space optics, channel models and hybrid modulation schemes: A review","volume":"119","author":"Magidi","year":"2021","journal-title":"Wirel. 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