{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T00:12:29Z","timestamp":1782951149651,"version":"3.54.5"},"reference-count":53,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,4,10]],"date-time":"2023-04-10T00:00:00Z","timestamp":1681084800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Research Foundation of Korea (NRF) grant funded by the Korea government (Ministry of Science and ICT (MSIT))","award":["022R1A2C1010121"],"award-info":[{"award-number":["022R1A2C1010121"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Long range (LoRa) is a low-power wide-area technology because it is eminent for robust long-distance, low-bitrate, and low-power communications in the unlicensed sub-GHz spectrum used for the Internet of things (IoT) networks. Recently, several multi-hop LoRa networks have proposed schemes with explicit relay nodes to partially mitigate the path loss and longer transmission time bottlenecks of the conventional single-hop LoRa by focusing more on coverage expansion. However, they do not consider improving the packet delivery success ratio (PDSR) and the packet reduction ratio (PRR) by using the overhearing technique. Thus, this paper proposes an implicit overhearing node-based multi-hop communication (IOMC) scheme in IoT LoRa networks, which exploits implicit relay nodes for performing the overhearing to promote relay operation while satisfying the duty cycle regulation. In IOMC, implicit relay nodes are selected as overhearing nodes (OHs) among end devices with a low spreading factor (SF) in order to improve PDSR and PRR for distant end devices (EDs). A theoretical framework for designing and determining the OH nodes to execute the relay operations was developed with consideration of the LoRaWAN MAC protocol. Simulation results verify that IOMC significantly increases the probability of successful transmission, performs best in high node density, and is more resilient to poor RSSI than the existing schemes.<\/jats:p>","DOI":"10.3390\/s23083874","type":"journal-article","created":{"date-parts":[[2023,4,11]],"date-time":"2023-04-11T01:33:03Z","timestamp":1681176783000},"page":"3874","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Implicit Overhearing Node-Based Multi-Hop Communication Scheme in IoT LoRa Networks"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8578-8818","authenticated-orcid":false,"given":"Dick","family":"Mugerwa","sequence":"first","affiliation":[{"name":"School of Information and Communication Engineering, Chungbuk National University, Cheongju 28644, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3971-0715","authenticated-orcid":false,"given":"Youngju","family":"Nam","sequence":"additional","affiliation":[{"name":"School of Information and Communication Engineering, Chungbuk National University, Cheongju 28644, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9410-7244","authenticated-orcid":false,"given":"Hyunseok","family":"Choi","sequence":"additional","affiliation":[{"name":"School of Information and Communication Engineering, Chungbuk National University, Cheongju 28644, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yongje","family":"Shin","sequence":"additional","affiliation":[{"name":"Research Institute for Computer and Information Communication, Chungbuk National University, Cheongju 28644, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0422-0647","authenticated-orcid":false,"given":"Euisin","family":"Lee","sequence":"additional","affiliation":[{"name":"School of Information and Communication Engineering, Chungbuk National University, Cheongju 28644, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"P\u0103tru, G.-C., Tranc\u0103, D.-C., Costea, C.-M., Rosner, D., and Rughini\u015f, R.-V. 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