{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,9]],"date-time":"2026-03-09T00:28:59Z","timestamp":1773016139934,"version":"3.50.1"},"reference-count":25,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2023,8,11]],"date-time":"2023-08-11T00:00:00Z","timestamp":1691712000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Education","award":["NRF-\n2018R1A6A1A03025109"],"award-info":[{"award-number":["NRF-\n2018R1A6A1A03025109"]}]},{"name":"Ministry of Education","award":["2023R1A2C1003928"],"award-info":[{"award-number":["2023R1A2C1003928"]}]},{"name":"Korea government (MSIT)","award":["NRF-\n2018R1A6A1A03025109"],"award-info":[{"award-number":["NRF-\n2018R1A6A1A03025109"]}]},{"name":"Korea government (MSIT)","award":["2023R1A2C1003928"],"award-info":[{"award-number":["2023R1A2C1003928"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The ultra-dense deployment (UDD) of small cells in 5G and beyond to enhance capacity and data rate is promising, but since user densities continually change, the static deployment of small cells can lead to wastes of capital, the underutilization of resources, and user dissatisfaction. This work proposes the use of Aerial Base Stations (ABSs) wherein small cells are mounted on Unmanned Aerial Vehicles (UAVs), which can be deployed to a set of candidate locations. Furthermore, based on the current user densities, this work studies the optimal placement of the ABSs, at a subset of potential candidate positions, to maximize the total received power and signal-to-interference ratio. The problems of the optimal placement for increasing received power and signal-to-interference ratio are formulated, and optimal placement solutions are designed. The proposed solutions compute the optimal candidate locations for the ABSs based on the current user densities. When the user densities change significantly, the proposed solutions can be re-executed to re-compute the optimal candidate locations for the ABSs, and hence the ABSs can be moved to their new candidate locations. Simulation results show that a 22% or more increase in the total received power can be achieved through the optimal placement of the Aerial BSs and that more than 60% users have more than 80% chance to have their individual received power increased.<\/jats:p>","DOI":"10.3390\/s23167098","type":"journal-article","created":{"date-parts":[[2023,8,11]],"date-time":"2023-08-11T12:10:23Z","timestamp":1691755823000},"page":"7098","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Dynamic Repositioning of Aerial Base Stations for Enhanced User Experience in 5G and Beyond"],"prefix":"10.3390","volume":"23","author":[{"given":"Shams Ur","family":"Rahman","sequence":"first","affiliation":[{"name":"Department of Computer Science, UET Mardan, Charsadda Road, Mardan 23200, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6441-4139","authenticated-orcid":false,"given":"Ajmal","family":"Khan","sequence":"additional","affiliation":[{"name":"Department of Artificial Intelligence and Big Data, Woosong University, 171 Dongdaejeon-ro, Dong-gu, Daejeon 34606, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8363-0179","authenticated-orcid":false,"given":"Muhammad","family":"Usman","sequence":"additional","affiliation":[{"name":"Department of Computer Science, UET Mardan, Charsadda Road, Mardan 23200, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4221-0877","authenticated-orcid":false,"given":"Muhammad","family":"Bilal","sequence":"additional","affiliation":[{"name":"Department of Computer Engineering, Hankuk University of Foreign Studies, Yongin-si 17035, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9427-4229","authenticated-orcid":false,"given":"You-Ze","family":"Cho","sequence":"additional","affiliation":[{"name":"School of Electronics and Electrical Engineering, Kyungpook National University, Daegu 41566, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7488-0915","authenticated-orcid":false,"given":"Hesham","family":"El-Sayed","sequence":"additional","affiliation":[{"name":"Computer and Network Engineering Department, College of Information Technology, United Arab Emirates University, Al Ain 16427, United Arab Emirates"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,11]]},"reference":[{"key":"ref_1","unstructured":"Harald, B., Blennerud, G., Burstedt, F., Chaisatien, W., and Karikyt, M. 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