{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:19:19Z","timestamp":1760145559345,"version":"build-2065373602"},"reference-count":54,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2024,8,15]],"date-time":"2024-08-15T00:00:00Z","timestamp":1723680000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003444","name":"BJUT Project","doi-asserted-by":"publisher","award":["40042001202218","47042B00202302","2020YFF0305401"],"award-info":[{"award-number":["40042001202218","47042B00202302","2020YFF0305401"]}],"id":[{"id":"10.13039\/501100003444","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Key Research and Development Program of China","award":["40042001202218","47042B00202302","2020YFF0305401"],"award-info":[{"award-number":["40042001202218","47042B00202302","2020YFF0305401"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>With the exponential growth of devices, particularly Internet of things (IoT) devices, connecting to wireless networks, existing networks face significant challenges. Spectral efficiency is crucial for uplink, which is the dominant form of asymmetrical network in today\u2019s communication landscape, in large-scale connectivity scenarios. In this paper, an uplink transmission scenario is considered and user equipment (UE) aggregation is employed, wherein some users act as cooperative nodes (CNs), and help to forward received data from other users requiring coverage extension, reliability improvement, and data\u2013rate enhancement. Non\u2013orthogonal multiple access (NOMA) technology is introduced to improve spectral efficiency. To reduce the interference impact to guarantee the data rate, one UE can be assisted by multiple CNs, and these CNs and corresponding assisted UEs are clustered into joint transmission pairs (JTPs). Interference-free transmission can be achieved within each JTP by utilizing different successive interference cancellation (SIC) decoding orders. To explore SIC gains and maximize data rates in NOMA\u2013based UE aggregation, we propose a primary user CN\u2013based channel\u2013sorting algorithm for JTP construction and apply a whale optimization algorithm for JTP power allocation. Additionally, a conflict graph is established among feasible JTPs, and a greedy strategy is employed to find the maximum weighted independent set (MWIS) of the conflict graph for subchannel allocation. Simulation results demonstrate that our joint collaborative NOMA (JC\u2013NOMA) design with two\u2013hop multi\u2013path UE aggregation significantly improves spectral efficiency and capacity under limited spectral resources.<\/jats:p>","DOI":"10.3390\/sym16081052","type":"journal-article","created":{"date-parts":[[2024,8,15]],"date-time":"2024-08-15T05:47:11Z","timestamp":1723700831000},"page":"1052","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Novel Design for Joint Collaborative NOMA Transmission with a Two\u2013Hop Multi\u2013Path UE Aggregation Mechanism"],"prefix":"10.3390","volume":"16","author":[{"given":"Xinqi","family":"Zhao","sequence":"first","affiliation":[{"name":"School of Information Science and Technology, Beijing University of Technology, Beijing 100124, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2799-6464","authenticated-orcid":false,"given":"Hua-Min","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Information Science and Technology, Beijing University of Technology, Beijing 100124, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3653-6531","authenticated-orcid":false,"given":"Shaofu","family":"Lin","sequence":"additional","affiliation":[{"name":"School of Information Science and Technology, Beijing University of Technology, Beijing 100124, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3146-5524","authenticated-orcid":false,"given":"Hui","family":"Li","sequence":"additional","affiliation":[{"name":"School of Information Science and Technology, Beijing University of Technology, Beijing 100124, China"}]},{"given":"Tao","family":"Chen","sequence":"additional","affiliation":[{"name":"MediaTek (Beijing), Beijing 100015, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1109\/MWC.2021.9615100","article-title":"6G: The next horizon: From connected people and things to connected intelligence","volume":"28","author":"Rong","year":"2021","journal-title":"IEEE Wirel. 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