{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T13:26:06Z","timestamp":1785331566332,"version":"3.55.0"},"reference-count":39,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,1,26]],"date-time":"2021-01-26T00:00:00Z","timestamp":1611619200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010661","name":"Horizon 2020 Framework Programme","doi-asserted-by":"publisher","award":["780229"],"award-info":[{"award-number":["780229"]}],"id":[{"id":"10.13039\/100010661","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>With worldwide deployment of LoRa\/LoRaWAN LPWAN networks in a large variety of applications, it is crucial to improve the robustness of LoRa channel access which is largely ALOHA-like to support environments with higher node density. This article presents extensive experiments on LoRa Channel Activity Detection and Capture Effect property in order to better understand how a competition-based channel access mechanisms can be optimized for LoRa LPWAN radio technology. In the light of these experimentation results, the contribution continues by identifying design guidelines for a channel access mechanism in LoRa and by proposing a channel access method with a lightweight collision avoidance mechanism that can operate without a reliable Clear Channel Assessment procedure. The proposed channel access mechanism has been implemented and preliminary tests show promising capabilities in increasing the Packet Delivery Rate in dense configurations.<\/jats:p>","DOI":"10.3390\/s21030825","type":"journal-article","created":{"date-parts":[[2021,1,26]],"date-time":"2021-01-26T08:29:16Z","timestamp":1611649756000},"page":"825","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":45,"title":["Dense Deployment of LoRa Networks: Expectations and Limits of Channel Activity Detection and Capture Effect for Radio Channel Access"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1936-8476","authenticated-orcid":false,"given":"Congduc","family":"Pham","sequence":"first","affiliation":[{"name":"LIUPPA Laboratory, University of Pau, 64000 Pau, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Muhammad","family":"Ehsan","sequence":"additional","affiliation":[{"name":"LIUPPA Laboratory, University of Pau, 64000 Pau, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.icte.2017.12.005","article-title":"A comparative study of LPWAN technologies for large-scale IoT deployment","volume":"5","author":"Mekki","year":"2019","journal-title":"ICT Express"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Yousuf, A.M., Rochester, E.M., Ousat, B., and Ghaderi, M. 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