{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:08:18Z","timestamp":1760242098917,"version":"build-2065373602"},"reference-count":24,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2018,12,19]],"date-time":"2018-12-19T00:00:00Z","timestamp":1545177600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["UID\/EEA\/50008\/2013"],"award-info":[{"award-number":["UID\/EEA\/50008\/2013"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Unmanned Aerial Vehicles (UAVs) can be a powerful tool for live (interactive) remote inspection of large-scale structures or areas of interest. Instead of manual, local, and labor-intensive inspections, we envision human operators working together with networks of semi-autonomous UAVs. The current state-of-the-art for low-delay high-throughput inter-vehicle networking relies on Time-Division Multiple Access (TDMA) techniques that require accurate synchronization among all network nodes. In this paper, we propose a delay-tolerant synchronization approach that converges to the correct order of the TDMA slots implemented over COTS WiFi in a fully-distributed way and without resorting to a global clock. This highly flexible solution allows building an ad-hoc aerial network based on a backbone of relaying UAVs. We show several alternatives to achieve this synchronization in a concrete aerial network and compare them in terms of slots\u2019 overlap, throughput, and packet delivery. The results show that these alternatives lead to trade-offs in the referenced metrics. The results also provide insight into the delays caused by buffering in the protocol stack and especially in the WiFi interface.<\/jats:p>","DOI":"10.3390\/s18124497","type":"journal-article","created":{"date-parts":[[2018,12,19]],"date-time":"2018-12-19T12:12:44Z","timestamp":1545221564000},"page":"4497","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["A Robust Approach to TDMA Synchronization in Aerial Networks"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1997-5484","authenticated-orcid":false,"given":"Luis Ramos","family":"Pinto","sequence":"first","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, R. Dr Roberto Frias, 4200-135 Porto, Portugal"},{"name":"CISTER Research Centre, R. Alfredo Allen 535, 4200-135 Porto, Portugal"},{"name":"Faculdade de Engenharia, Universidade do Porto, R. Dr Roberto Frias, 4200-135 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9544-3028","authenticated-orcid":false,"given":"Luis","family":"Almeida","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, R. Dr Roberto Frias, 4200-135 Porto, Portugal"},{"name":"CISTER Research Centre, R. Alfredo Allen 535, 4200-135 Porto, Portugal"},{"name":"Faculdade de Engenharia, Universidade do Porto, R. Dr Roberto Frias, 4200-135 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2018,12,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1123","DOI":"10.1109\/COMST.2015.2495297","article-title":"Survey of Important Issues in UAV Communication Networks","volume":"18","author":"Gupta","year":"2016","journal-title":"IEEE Commun. Surv. Tutor."},{"key":"ref_2","unstructured":"(2018, December 01). Wild Life Drones. 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