{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T09:14:49Z","timestamp":1774862089960,"version":"3.50.1"},"reference-count":48,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,3,29]],"date-time":"2026-03-29T00:00:00Z","timestamp":1774742400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The deployment of Wireless Sensor Networks (WSNs) remains challenging and time consuming due to the manual commissioning, configuration, and maintenance of resource-constrained Internet of Things (IoT) devices. Achieving precise network-wide time synchronization in such systems further increases this deployment complexity. This paper presents a novel Real-Time Operating System (RTOS)-integrated time synchronization method that distributes an absolute Coordinated Universal Time (UTC) reference across the network using a single Global Navigation Satellite System (GNSS)-enabled host. The method extends the semantics of the RTOS tick count by directly linking it to a global time reference. Consequently, sensor nodes obtain a notion of UTC time and can execute time-critical tasks at precisely defined moments without requiring a dedicated Real-Time Clock (RTC) or GNSS module on each sensor node. This design reduces both hardware cost and overall system complexity. Experimental results obtained on custom-developed hardware running FreeRTOS demonstrate a task synchronization error below \u00b130 \u03bcs between the GNSS reference and a sensor node operating at a clock frequency of 32 MHz. Such precise network-wide synchronization enables more efficient channel utilization, reduces power consumption, and improves the accuracy of both local and coordinated task execution across multiple devices in WSNs. It therefore serves as a key enabler for self-deployable WSNs.<\/jats:p>","DOI":"10.3390\/s26072121","type":"journal-article","created":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T08:22:36Z","timestamp":1774858956000},"page":"2121","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["RTOS-Integrated Time Synchronization for Self-Deployable Wireless Sensor Networks"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7525-1179","authenticated-orcid":false,"given":"Sarah","family":"Goossens","sequence":"first","affiliation":[{"name":"WaveCore, Department of Electrical Engineering (ESAT), KU Leuven, Ghent Campus, 9000 Ghent, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6385-253X","authenticated-orcid":false,"given":"Valentijn","family":"De Smedt","sequence":"additional","affiliation":[{"name":"ECS, Department of Electrical Engineering (ESAT), KU Leuven, 2440 Geel, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8172-9650","authenticated-orcid":false,"given":"Lieven","family":"De Strycker","sequence":"additional","affiliation":[{"name":"WaveCore, Department of Electrical Engineering (ESAT), KU Leuven, Ghent Campus, 9000 Ghent, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9158-9628","authenticated-orcid":false,"given":"Liesbet","family":"Van der Perre","sequence":"additional","affiliation":[{"name":"WaveCore, Department of Electrical Engineering (ESAT), KU Leuven, Ghent Campus, 9000 Ghent, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,29]]},"reference":[{"key":"ref_1","unstructured":"Sparks, P. 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