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Since the number of on\u2010ground user terminals is usually much higher than the number of on\u2010board LEO satellite antennas, user scheduling becomes a fundamental task. We accomplish user scheduling by grouping users into clusters. Users within the same cluster are served by the satellite at the same time by means of space division multiplexing via location\u2010based feed space digital beamforming. Each cluster is then assigned to a distinct time slot and served by means of time division multiplexing. Given the full frequency reuse nature of the system, we design user scheduling algorithms with the goal of maximizing the average per\u2010user throughput while minimizing the co\u2010channel interference and preserving fairness among users. To this aim, we propose in this paper (a) a distance\u2010based iterative graph\u2010based scheduler based on the maximum clique approach and (b) a distance\u2010based implementation of the multiple antenna downlink orthogonal user clustering algorithm. For both these schedulers, the great circle distance between the users is employed as a dissimilarity metric to compute the user adjacency matrix, avoiding the need for the transmission of downlink pilots for channel state information estimation. To further validate our analysis, the proposed approaches are compared with (a) channel state information\u2010based graph and maximum clique approach and (b) original multiple antenna downlink orthogonal user clustering algorithm. Extensive simulations assess the achievable per\u2010user throughput and signal\u2010to\u2010noise plus interference ratio achieved by the proposed schedulers, highlighting the impact that the distance\u2010based metric has on the system performance. This study provides valuable insights into the effective use of user scheduling algorithms.<\/jats:p>","DOI":"10.1002\/sat.70006","type":"journal-article","created":{"date-parts":[[2025,9,3]],"date-time":"2025-09-03T12:17:50Z","timestamp":1756901870000},"page":"275-287","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Location\u2010Assisted Graph\u2010Based User Scheduling in Multi\u2010User MIMO LEO NTN Systems"],"prefix":"10.1002","volume":"44","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-3986-2072","authenticated-orcid":false,"given":"Bilal","family":"Ahmad","sequence":"first","affiliation":[{"name":"Department of Electrical, Electronic, and Information Engineering University of Bologna  Bologna Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7714-9191","authenticated-orcid":false,"given":"Daniel\u00a0Gaetano","family":"Riviello","sequence":"additional","affiliation":[{"name":"CNR\u2010IEIIT, Istituto di Elettronica e Ingegneria dell'Informazione e delle Telecomunicazioni Consiglio Nazionale delle Ricerche  Torino Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0266-1788","authenticated-orcid":false,"given":"Bruno","family":"De\u00a0Filippo","sequence":"additional","affiliation":[{"name":"Department of Electrical, Electronic, and Information Engineering University of Bologna  Bologna Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4480-0010","authenticated-orcid":false,"given":"Alessandro","family":"Guidotti","sequence":"additional","affiliation":[{"name":"National Inter\u2010University Consortium for Telecommunications (CNIT) University of Bologna Research Unit  Bologna Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4475-5718","authenticated-orcid":false,"given":"Alessandro","family":"Vanelli\u2010Coralli","sequence":"additional","affiliation":[{"name":"Department of Electrical, Electronic, and Information Engineering University of Bologna  Bologna Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2025,9,3]]},"reference":[{"key":"e_1_2_8_2_1","doi-asserted-by":"publisher","DOI":"10.1109\/MNET.011.2100191"},{"key":"e_1_2_8_3_1","doi-asserted-by":"publisher","DOI":"10.1109\/ACCESS.2024.3389459"},{"key":"e_1_2_8_4_1","doi-asserted-by":"crossref","unstructured":"A.Di Mezza A.Vanelli Coralli A.Guidotti T.Foggi G.Colavolpe andG.Montorsi \u201c5G4SPACE: Adaptation of 5G Radio Access Technology for Satcom\u201d 2019 International Symposium on Advanced Electrical and Communication Technologies (ISAECT) Rome Italy 2019 pp.1\u20133 https:\/\/doi.org\/10.1109\/ISAECT47714.2019.9069675.","DOI":"10.1109\/ISAECT47714.2019.9069675"},{"key":"e_1_2_8_5_1","doi-asserted-by":"publisher","DOI":"10.1109\/COMST.2016.2618870"},{"key":"e_1_2_8_6_1","doi-asserted-by":"crossref","unstructured":"A.Ugolini Y.Zanettini A.Piemontese A.Vanelli\u2010CoralliandG.Colavolpe \u201cEfficient Satellite Systems Based on Interference Management and Exploitation\u201d 2016 50th Asilomar Conference on Signals Systems and Computers Pacific Grove CA USA 2016 pp.492\u2013496 https:\/\/doi.org\/10.1109\/ACSSC.2016.7869088.","DOI":"10.1109\/ACSSC.2016.7869088"},{"key":"e_1_2_8_7_1","doi-asserted-by":"publisher","DOI":"10.1002\/sat.1312"},{"key":"e_1_2_8_8_1","doi-asserted-by":"publisher","DOI":"10.1109\/TVT.2011.2165976"},{"key":"e_1_2_8_9_1","doi-asserted-by":"crossref","unstructured":"M.VzquezandA. 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