{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T02:22:48Z","timestamp":1783650168121,"version":"3.55.0"},"reference-count":37,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2019,6,3]],"date-time":"2019-06-03T00:00:00Z","timestamp":1559520000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61871348"],"award-info":[{"award-number":["61871348"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The internet of things (IoT) is becoming more indispensable in modern society as the further development and maturity of information technology progresses. However the exponential growth of IoT devices leads to severe energy consumption. As a technology with broad application prospects, simultaneous wireless information and power transfer (SWIPT) enables IoT devices to harvest energy from receiving radio frequency (RF) signals while ensuring information transmission. In this paper, we investigate the transmission rate optimization problem for a dual-hop multi-relay IoT system, where a decode-and-forward (DF) relay supports the SWIPT technique. We jointly optimize the resource including power and subcarrier allocation, to maximize the system transmission rate. The time-sharing strategy and Lagrange dual method are used to solve this optimization problem. Simulation results reveal that the proposed algorithm has a larger transmission rate than other benchmark algorithms when ensuring each relay has no additional energy supply. Specifically, the proposed algorithm improves the information transmission rate by 2.8%, 3.4% and 43% compared with other algorithms in the case of five relays when the source\u2019s power is equal to 0.5 W, respectively.<\/jats:p>","DOI":"10.3390\/s19112536","type":"journal-article","created":{"date-parts":[[2019,6,3]],"date-time":"2019-06-03T11:31:01Z","timestamp":1559561461000},"page":"2536","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Joint Resource Optimization in Simultaneous Wireless Information and Power Transfer (SWIPT) Enabled Multi-Relay Internet of Things (IoT) System"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8919-0327","authenticated-orcid":false,"given":"Weidang","family":"Lu","sequence":"first","affiliation":[{"name":"College of Information Engineering, Zhejiang University of Technology, Hangzhou 310014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guangzhe","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Information Engineering, Zhejiang University of Technology, Hangzhou 310014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peiyuan","family":"Si","sequence":"additional","affiliation":[{"name":"College of Information Engineering, Zhejiang University of Technology, Hangzhou 310014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guanghua","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering and Information, Northeast Petroleum University, Daqing 163318, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bo","family":"Li","sequence":"additional","affiliation":[{"name":"School of Information and Electrical Engineering, Harbin Institute of Technology, Weihai 264209, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hong","family":"Peng","sequence":"additional","affiliation":[{"name":"College of Information Engineering, Zhejiang University of Technology, Hangzhou 310014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,6,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5436","DOI":"10.1109\/TII.2018.2858142","article-title":"Nonorthogonal interleave-grid multiple access scheme for industrial internet of things in 5G network","volume":"14","author":"Hu","year":"2018","journal-title":"IEEE Trans. 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