{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,22]],"date-time":"2025-10-22T18:12:06Z","timestamp":1761156726330,"version":"build-2065373602"},"reference-count":31,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2019,8,8]],"date-time":"2019-08-08T00:00:00Z","timestamp":1565222400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004919","name":"King Abdulaziz City for Science and Technology","doi-asserted-by":"publisher","award":["PC-37-66"],"award-info":[{"award-number":["PC-37-66"]}],"id":[{"id":"10.13039\/501100004919","id-type":"DOI","asserted-by":"publisher"}]},{"name":"European Union\u2019s Horizon 2020 Research and Innovation Program","award":["668995"],"award-info":[{"award-number":["668995"]}]},{"name":"European Union Regional Development Fund in the framework of the Tallinn University of Technology Development Program 2016-2022","award":["2016-2022"],"award-info":[{"award-number":["2016-2022"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In recent years, Energy Efficiency (EE) has become a critical design metric for cellular systems. In order to achieve EE, a fine balance between throughput and fairness must also be ensured. To this end, in this paper we have presented various resource block (RB) allocation schemes in relay-assisted Long Term Evolution-Advanced (LTE-A) networks. Driven by equal power and Bisection-based Power Allocation (BOPA) algorithm, the Maximum Throughput (MT) and an alternating MT and proportional fairness (PF)-based SAMM (abbreviated with Authors\u2019 names) RB allocation scheme is presented for a single relay. In the case of multiple relays, the dependency of RB and power allocation on relay deployment and users\u2019 association is first addressed through a k-mean clustering approach. Secondly, to reduce the computational cost of RB and power allocation, a two-step neural network (NN) process (SAMM NN) is presented that uses SAMM-based unsupervised learning for RB allocation and BOPA-based supervised learning for power allocation. The results for all the schemes are compared in terms of EE and user throughput. For a single relay, SAMM BOPA offers the best EE, whereas SAMM equal power provides the best fairness. In the case of multiple relays, the results indicate SAMM NN achieves better EE compared to SAMM equal power and BOPA, and it also achieves better throughput fairness compared to MT equal power and MT BOPA.<\/jats:p>","DOI":"10.3390\/s19163461","type":"journal-article","created":{"date-parts":[[2019,8,8]],"date-time":"2019-08-08T11:05:32Z","timestamp":1565262332000},"page":"3461","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["A Machine Learning Approach to Achieving Energy Efficiency in Relay-Assisted LTE-A Downlink System"],"prefix":"10.3390","volume":"19","author":[{"given":"Hammad","family":"Hassan","sequence":"first","affiliation":[{"name":"School of Electrical Engineering and Computer Science, National University of Sciences &amp; Technology (NUST), Islamabad 44000, Pakistan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0937-2359","authenticated-orcid":false,"given":"Irfan","family":"Ahmed","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Higher Colleges of Technology, Ruwais Campus 12389, UAE"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4758-7895","authenticated-orcid":false,"given":"Rizwan","family":"Ahmad","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering and Computer Science, National University of Sciences &amp; Technology (NUST), Islamabad 44000, Pakistan"}]},{"given":"Hedi","family":"Khammari","sequence":"additional","affiliation":[{"name":"College of Computers and Information Technology, Taif University, Taif 21974, Saudi Arabia"}]},{"given":"Ghulam","family":"Bhatti","sequence":"additional","affiliation":[{"name":"College of Computers and Information Technology, Taif University, Taif 21974, Saudi Arabia"}]},{"given":"Waqas","family":"Ahmed","sequence":"additional","affiliation":[{"name":"Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad 45650, Pakistan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1055-7959","authenticated-orcid":false,"given":"Muhammad Mahtab","family":"Alam","sequence":"additional","affiliation":[{"name":"Thomas Johann Seebeck Department of Electronics, Tallinn University of Technology, Tallinn 19086, Estonia"}]}],"member":"1968","published-online":{"date-parts":[[2019,8,8]]},"reference":[{"key":"ref_1","first-page":"42","article-title":"Energy efficiency enhancements in radio access networks","volume":"81","author":"Edler","year":"2004","journal-title":"Ericsson Rev."},{"key":"ref_2","unstructured":"Kumar, R., and Mieritz, L. 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