{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:43:49Z","timestamp":1760150629126,"version":"build-2065373602"},"reference-count":30,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2023,12,13]],"date-time":"2023-12-13T00:00:00Z","timestamp":1702425600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Council for Scientific and Technological Development (CNPq) of Brazil","award":["405301\/2021-9","405760\/2021-3"],"award-info":[{"award-number":["405301\/2021-9","405760\/2021-3"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Fifth-generation (5G) and beyond networks are expected to serve large numbers of user equipments (UEs). Grant-based random access (RA) protocols are efficient when serving human users, typically with large data volumes to transmit. The strongest user collision resolution (SUCRe) is the first protocol that effectively uses the many antennas at the 5G base station (BS) to improve connectivity performance. In this paper, our proposal involves substituting the retransmission rule of the SUCRe protocol with a neural network (NN) to enhance the identification of the strongest user and resolve collisions in a decentralized manner on the UEs\u2019 side. The proposed NN-based procedure is trained offline, admitting different congestion levels of the system, aiming to obtain a single setup able to operate with different numbers of UEs. The numerical results indicate that our method attains substantial connectivity performance improvements compared to other protocols without requiring additional complexity or overhead. In addition, the proposed approach is robust regarding variations in the number of BS antennas and transmission power while improving energy efficiency by requiring fewer attempts on the RA stage.<\/jats:p>","DOI":"10.3390\/s23249805","type":"journal-article","created":{"date-parts":[[2023,12,13]],"date-time":"2023-12-13T12:00:37Z","timestamp":1702468837000},"page":"9805","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Neural Network-Based Random Access Protocol for Crowded Massive MIMO Systems"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0087-6873","authenticated-orcid":false,"given":"Felipe Augusto Dutra","family":"Bueno","sequence":"first","affiliation":[{"name":"Electrical Engineering Department, Federal University of Technology PR, Av. Alberto Carazzai, 1640, Corn\u00e9lio Proc\u00f3pio 86300 000, PR, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4085-070X","authenticated-orcid":false,"given":"C\u00e9zar Fumio","family":"Yamamura","sequence":"additional","affiliation":[{"name":"Electrical Engineering Department, Federal University of Technology PR, Av. Alberto Carazzai, 1640, Corn\u00e9lio Proc\u00f3pio 86300 000, PR, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7169-954X","authenticated-orcid":false,"given":"Paulo Rog\u00e9rio","family":"Scalassara","sequence":"additional","affiliation":[{"name":"Electrical Engineering Department, Federal University of Technology PR, Av. Alberto Carazzai, 1640, Corn\u00e9lio Proc\u00f3pio 86300 000, PR, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8678-2805","authenticated-orcid":false,"given":"Taufik","family":"Abr\u00e3o","sequence":"additional","affiliation":[{"name":"Electrical Engineering Department, State University of Londrina, Rod. Celso Garcia Cid-PR445, Londrina 86057 970, PR, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0980-8220","authenticated-orcid":false,"given":"Jos\u00e9 Carlos","family":"Marinello","sequence":"additional","affiliation":[{"name":"Electrical Engineering Department, Federal University of Technology PR, Av. Alberto Carazzai, 1640, Corn\u00e9lio Proc\u00f3pio 86300 000, PR, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,12,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"615","DOI":"10.1109\/JSAC.2020.3019724","article-title":"Massive Access for 5G and Beyond","volume":"39","author":"Chen","year":"2021","journal-title":"IEEE J. Sel. Areas Commun."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"3590","DOI":"10.1109\/TWC.2010.092810.091092","article-title":"Noncooperative Cellular Wireless with Unlimited Numbers of Base Station Antennas","volume":"9","author":"Marzetta","year":"2010","journal-title":"IEEE Trans. Wirel. Commun."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"24","DOI":"10.1109\/MCOMSTD.2017.1700042","article-title":"NR: The New 5G Radio Access Technology","volume":"1","author":"Parkvall","year":"2017","journal-title":"IEEE Commun. Stand. 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