{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T00:48:18Z","timestamp":1760057298619,"version":"build-2065373602"},"reference-count":27,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2025,1,31]],"date-time":"2025-01-31T00:00:00Z","timestamp":1738281600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China (NSFC)","award":["61872385","61972417","ZR2020MF005"],"award-info":[{"award-number":["61872385","61972417","ZR2020MF005"]}]},{"name":"Shandong Provincial Natural Science Foundation, China","award":["61872385","61972417","ZR2020MF005"],"award-info":[{"award-number":["61872385","61972417","ZR2020MF005"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Information"],"abstract":"<jats:p>Integrating Non-Orthogonal Multiple Access (NOMA) backscatter with Cognitive Radio (CR) can effectively alleviate the pressure of large-scale Internet of Things (IoT) device connections while reducing power consumption. In the downlink of NOMA backscatter-based CR networks (NB-CR), most researchers only consider the case of a single backscatter device (BD), ignoring the fact that multiple BDs can prolong device usage and enhance system robustness. The resource allocation (RA) problem is crucial in the downlink of NB-CR networks. Most existing RA algorithms focus on system throughput but rarely consider energy efficiency (EE). In this paper, we propose the RA problem for downlink communication (NBCR-RA) in NB-CR networks with multiple BDs. We jointly optimize power allocation coefficients and reflection coefficients (RCs) to maximize EE. We model the NBCR-RA problem as a non-convex problem and divide it into two subproblems: power allocation optimization and RC optimization. Firstly, we propose a Lagrange-based power allocation optimization (L-PA) algorithm to obtain the optimal power allocation coefficients. Secondly, we design an RC optimization algorithm, PS-RC, based on a particle swarm algorithm to determine the optimal RCs. Finally, we validate the superiority of L-PA and PS-RC algorithms in terms of EE. Through multiple experiments, we obtained a 95% confidence interval of [10.5552, 10.6465].<\/jats:p>","DOI":"10.3390\/info16020098","type":"journal-article","created":{"date-parts":[[2025,1,31]],"date-time":"2025-01-31T08:05:41Z","timestamp":1738310741000},"page":"98","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Research on Resource Allocation Algorithm for Non-Orthogonal Multiple Access Backscatter-Based Cognitive Radio Networks"],"prefix":"10.3390","volume":"16","author":[{"given":"Tingpei","family":"Huang","sequence":"first","affiliation":[{"name":"Qingdao Institute of Software, College of Computer Science and Technology, China University of Petroleum East China, Qingdao 266580, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tiantian","family":"Zhang","sequence":"additional","affiliation":[{"name":"Qingdao Institute of Software, College of Computer Science and Technology, China University of Petroleum East China, Qingdao 266580, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bairen","family":"Zhang","sequence":"additional","affiliation":[{"name":"Qingdao Institute of Software, College of Computer Science and Technology, China University of Petroleum East China, Qingdao 266580, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jianhang","family":"Liu","sequence":"additional","affiliation":[{"name":"Qingdao Institute of Software, College of Computer Science and Technology, China University of Petroleum East China, Qingdao 266580, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shibao","family":"Li","sequence":"additional","affiliation":[{"name":"College of Oceanography and Space Informatics, China University of Petroleum East China, Qingdao 266580, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"894","DOI":"10.1109\/JPROC.2009.2015717","article-title":"Breaking Spectrum Gridlock with Cognitive Radios: An Information Theoretic Perspective","volume":"97","author":"Goldsmith","year":"2009","journal-title":"Proc. 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Proceedings of the 2022 IEEE Global Communications Conference, Rio de Janeiro, Brazil.","DOI":"10.1109\/GLOBECOM48099.2022.10001031"}],"container-title":["Information"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2078-2489\/16\/2\/98\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T16:24:56Z","timestamp":1760027096000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2078-2489\/16\/2\/98"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,1,31]]},"references-count":27,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2025,2]]}},"alternative-id":["info16020098"],"URL":"https:\/\/doi.org\/10.3390\/info16020098","relation":{},"ISSN":["2078-2489"],"issn-type":[{"type":"electronic","value":"2078-2489"}],"subject":[],"published":{"date-parts":[[2025,1,31]]}}}