{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,10]],"date-time":"2026-03-10T15:19:55Z","timestamp":1773155995554,"version":"3.50.1"},"reference-count":69,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2020,11,30]],"date-time":"2020-11-30T00:00:00Z","timestamp":1606694400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100010801","name":"Xunta de Galicia","doi-asserted-by":"publisher","award":["ED431C 2020\/15, ED431G490 2019\/01"],"award-info":[{"award-number":["ED431C 2020\/15, ED431G490 2019\/01"]}],"id":[{"id":"10.13039\/501100010801","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Agencia Estatal de Investigaci\u00f3n of Spain and ERDF funds of the EU (FEDER Galicia 2014-2020 &amp; AEI\/FEDER Programs, UE)","award":["RTI2018-095499-B-C31, TEC2016-75067-C4-1-R, RED2018-102668-T and PID2019-104958RB-C42"],"award-info":[{"award-number":["RTI2018-095499-B-C31, TEC2016-75067-C4-1-R, RED2018-102668-T and PID2019-104958RB-C42"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Climate change is driving new solutions to manage water more efficiently. Such solutions involve the development of smart irrigation systems where Internet of Things (IoT) nodes are deployed throughout large areas. In addition, in the mentioned areas, wireless communications can be difficult due to the presence of obstacles and metallic objects that block electromagnetic wave propagation totally or partially. This article details the development of a smart irrigation system able to cover large urban areas thanks to the use of Low-Power Wide-Area Network (LPWAN) sensor nodes based on LoRa and LoRaWAN. IoT nodes collect soil temperature\/moisture and air temperature data, and control water supply autonomously, either by making use of fog computing gateways or by relying on remote commands sent from a cloud. Since the selection of IoT node and gateway locations is essential to have good connectivity and to reduce energy consumption, this article uses an in-house 3D-ray launching radio-planning tool to determine the best locations in real scenarios. Specifically, this paper provides details on the modeling of a university campus, which includes elements like buildings, roads, green areas, or vehicles. In such a scenario, simulations and empirical measurements were performed for two different testbeds: a LoRaWAN testbed that operates at 868 MHz and a testbed based on LoRa with 433 MHz transceivers. All the measurements agree with the simulation results, showing the impact of shadowing effects and material features (e.g., permittivity, conductivity) in the electromagnetic propagation of near-ground and underground LoRaWAN communications. Higher RF power levels are observed for 433 MHz due to the higher transmitted power level and the lower radio propagation losses, and even in the worst gateway location, the received power level is higher than the sensitivity threshold (\u2212148 dBm). Regarding water consumption, the provided estimations indicate that the proposed smart irrigation system is able to reduce roughly 23% of the amount of used water just by considering weather forecasts. The obtained results provide useful guidelines for future smart irrigation developers and show the radio planning tool accuracy, which allows for optimizing the sensor network topology and the overall performance of the network in terms of coverage, cost, and energy consumption.<\/jats:p>","DOI":"10.3390\/s20236865","type":"journal-article","created":{"date-parts":[[2020,11,30]],"date-time":"2020-11-30T20:10:22Z","timestamp":1606767022000},"page":"6865","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":74,"title":["Design, Implementation, and Empirical Validation of an IoT Smart Irrigation System for Fog Computing Applications Based on LoRa and LoRaWAN Sensor Nodes"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4068-8842","authenticated-orcid":false,"given":"Iv\u00e1n","family":"Froiz-M\u00edguez","sequence":"first","affiliation":[{"name":"Department of Computer Engineering, Faculty of Computer Science, Universidade da Coru\u00f1a, 15071 A Coru\u00f1a, Spain"},{"name":"Centro de investigaci\u00f3n CITIC, Universidade da Coru\u00f1a, 15071 A Coru\u00f1a, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8411-1928","authenticated-orcid":false,"given":"Peio","family":"Lopez-Iturri","sequence":"additional","affiliation":[{"name":"Department of Electric, Electronic and Communication Engineering, Public University of Navarre, 31006 Pamplona, Spain"},{"name":"Institute of Smart Cities, Public University of Navarre, 31006 Pamplona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4991-6808","authenticated-orcid":false,"given":"Paula","family":"Fraga-Lamas","sequence":"additional","affiliation":[{"name":"Department of Computer Engineering, Faculty of Computer Science, Universidade da Coru\u00f1a, 15071 A Coru\u00f1a, Spain"},{"name":"Centro de investigaci\u00f3n CITIC, Universidade da Coru\u00f1a, 15071 A Coru\u00f1a, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7880-8224","authenticated-orcid":false,"given":"Mikel","family":"Celaya-Echarri","sequence":"additional","affiliation":[{"name":"School of Engineering and Sciences, Tecnologico de Monterrey, 64849 Monterrey, NL, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8608-1088","authenticated-orcid":false,"given":"\u00d3scar","family":"Blanco-Novoa","sequence":"additional","affiliation":[{"name":"Department of Computer Engineering, Faculty of Computer Science, Universidade da Coru\u00f1a, 15071 A Coru\u00f1a, Spain"},{"name":"Centro de investigaci\u00f3n CITIC, Universidade da Coru\u00f1a, 15071 A Coru\u00f1a, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3821-0105","authenticated-orcid":false,"given":"Leyre","family":"Azpilicueta","sequence":"additional","affiliation":[{"name":"School of Engineering and Sciences, Tecnologico de Monterrey, 64849 Monterrey, NL, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4911-9753","authenticated-orcid":false,"given":"Francisco","family":"Falcone","sequence":"additional","affiliation":[{"name":"Department of Electric, Electronic and Communication Engineering, Public University of Navarre, 31006 Pamplona, Spain"},{"name":"Institute of Smart Cities, Public University of Navarre, 31006 Pamplona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2179-5917","authenticated-orcid":false,"given":"Tiago M.","family":"Fern\u00e1ndez-Caram\u00e9s","sequence":"additional","affiliation":[{"name":"Department of Computer Engineering, Faculty of Computer Science, Universidade da Coru\u00f1a, 15071 A Coru\u00f1a, Spain"},{"name":"Centro de investigaci\u00f3n CITIC, Universidade da Coru\u00f1a, 15071 A Coru\u00f1a, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,30]]},"reference":[{"key":"ref_1","unstructured":"(2020, September 30). 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