{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,24]],"date-time":"2025-10-24T16:44:07Z","timestamp":1761324247020,"version":"build-2065373602"},"reference-count":35,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2019,11,4]],"date-time":"2019-11-04T00:00:00Z","timestamp":1572825600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["NRF-2019R1F1A1047989"],"award-info":[{"award-number":["NRF-2019R1F1A1047989"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents cooperative transmission (CT), where multiple relays are used to achieve array and diversity gains, as an enabling technology for Internet of Things (IoT) networks with hardware-limited devices. We investigate a channel coding aided decode-and-forward (DF) relaying network, considering a two-hop multiple-relay network, where the data transmission between the source and the destination is realized with the help of DF relays. Low density parity check (LDPC) codes are adopted as forward error correction (FEC) codes to encode and decode the data both at the source and relays. We consider both fixed and variable code rates depending upon the quality-of-service (QoS) provisioning such as spectral efficiency and maximum energy efficiency. Furthermore, an optimal power allocation scheme is studied for the cooperative system under the energy efficiency constraint. We present the simulation results of our proposed scheme, compared with conventional methods, which show that if decoupled code rates are used on both hops then a trade-off has to be maintained between system complexity, transmission delay, and bit error rate (BER).<\/jats:p>","DOI":"10.3390\/s19214793","type":"journal-article","created":{"date-parts":[[2019,11,4]],"date-time":"2019-11-04T10:49:07Z","timestamp":1572864547000},"page":"4793","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Energy Efficiency of a Decode-and-Forward Multiple-Relay Network with Rate Adaptive LDPC Codes"],"prefix":"10.3390","volume":"19","author":[{"given":"Bushra Bashir","family":"Chaoudhry","sequence":"first","affiliation":[{"name":"Department of Telecommunications, University of Stuttgart, 70569 Stuttgart, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8572-7377","authenticated-orcid":false,"given":"Syed Ali","family":"Hassan","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering &amp; Computer Science (SEECS), National University of Sciences &amp; Technology (NUST), Islamabad 44000, Pakistan"}]},{"given":"Joachim","family":"Speidel","sequence":"additional","affiliation":[{"name":"Department of Telecommunications, University of Stuttgart, 70569 Stuttgart, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1901-2784","authenticated-orcid":false,"given":"Haejoon","family":"Jung","sequence":"additional","affiliation":[{"name":"Department of Information &amp; Telecommunication Engineering, Incheon National University, Incheon 22012, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1109\/MCOM.2017.1600514","article-title":"Internet-of-Things-based smart cities: Recent advances and challenges","volume":"55","author":"Mehmood","year":"2017","journal-title":"IEEE Commun. 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