{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,16]],"date-time":"2026-01-16T04:24:24Z","timestamp":1768537464884,"version":"3.49.0"},"reference-count":24,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2024,12,5]],"date-time":"2024-12-05T00:00:00Z","timestamp":1733356800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the science and technology project of the state grid corporation of China","award":["5700-202356629A-3-2-ZN"],"award-info":[{"award-number":["5700-202356629A-3-2-ZN"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>This paper investigated a non-orthogonal multiple access (NOMA)-based integrated satellite\u2013terrestrial network (ISTN), where each user can select to access a terrestrial base station (BS) or the satellite according to the capacity of BS and their individual transmission requirements. A two-stage algorithm is proposed to solve the achievable sum rate maximizing resource optimization problem. In the first stage, user associations are determined based on individual preference lists and the backhaul capacities of the access points (APs). In the second stage, the power allocation, and the receiving beamforming vectors are optimized alternately. Within each iteration, the closed-form solution for the transmit power is derived. Simulation results show the effectiveness of the proposed algorithm and the benefits brought by NOMA. When the backhaul link capacity of terrestrial BSs is sufficient, users (UEs) prefer to access these BSs. Otherwise, the satellite can offer QoS guarantees to UEs. Furthermore, the overall system performance reaches its optimum when the number of UEs in the system matches the number of receive antennas at the APs.<\/jats:p>","DOI":"10.3390\/e26121055","type":"journal-article","created":{"date-parts":[[2024,12,5]],"date-time":"2024-12-05T04:13:03Z","timestamp":1733371983000},"page":"1055","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Joint User Association, Power Allocation and Beamforming for NOMA-Based Integrated Satellite\u2013Terrestrial Networks"],"prefix":"10.3390","volume":"26","author":[{"given":"Peizhe","family":"Xin","sequence":"first","affiliation":[{"name":"State Grid Economic and Technological Research Institute Co., Ltd., 102209 Beijing, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4706-9115","authenticated-orcid":false,"given":"Zihao","family":"Fu","sequence":"additional","affiliation":[{"name":"State Grid Economic and Technological Research Institute Co., Ltd., 102209 Beijing, China"}]},{"given":"Zhiyi","family":"Chen","sequence":"additional","affiliation":[{"name":"State Grid Economic and Technological Research Institute Co., Ltd., 102209 Beijing, China"}]},{"given":"Jing","family":"Jiang","sequence":"additional","affiliation":[{"name":"State Grid Economic and Technological Research Institute Co., Ltd., 102209 Beijing, China"}]},{"given":"Jing","family":"Zou","sequence":"additional","affiliation":[{"name":"State Grid Economic and Technological Research Institute Co., Ltd., 102209 Beijing, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6978-370X","authenticated-orcid":false,"given":"Yu","family":"Zhang","sequence":"additional","affiliation":[{"name":"Information Materials and Intelligent Sensing Laboratory of Anhui Province, Anhui University, Hefei 230601, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0274-0478","authenticated-orcid":false,"given":"Xinyue","family":"Hu","sequence":"additional","affiliation":[{"name":"Information Materials and Intelligent Sensing Laboratory of Anhui Province, Anhui University, Hefei 230601, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1948","DOI":"10.1109\/LWC.2024.3397347","article-title":"Energy Efficiency Design in RIS-Assisted Satellite\u2013Terrestrial Integrated Networks with NOMA","volume":"13","author":"Lv","year":"2024","journal-title":"IEEE Wirel. 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