{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,22]],"date-time":"2026-01-22T07:04:50Z","timestamp":1769065490644,"version":"3.49.0"},"reference-count":68,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,4,12]],"date-time":"2021-04-12T00:00:00Z","timestamp":1618185600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Commission","doi-asserted-by":"publisher","award":["828841"],"award-info":[{"award-number":["828841"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","award":["0181 NANOEATERS 1 EP"],"award-info":[{"award-number":["0181 NANOEATERS 1 EP"]}],"id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]},{"name":"CCDR-N","award":["NORTE-01-0145-FEDER-000019"],"award-info":[{"award-number":["NORTE-01-0145-FEDER-000019"]}]},{"name":"Conseller\u00eda de Educaci\u00f3n, Universidade e Formaci\u00f3n Profesiona","award":["ED431B 2018\/57"],"award-info":[{"award-number":["ED431B 2018\/57"]}]},{"DOI":"10.13039\/501100010198","name":"Ministerio de Econom\u00eda, Industria y Competitividad, Gobierno de Espa\u00f1a","doi-asserted-by":"publisher","award":["FIS2017-83762-P"],"award-info":[{"award-number":["FIS2017-83762-P"]}],"id":[{"id":"10.13039\/501100010198","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The age of the Internet of Things (IoT) and smart cities calls for low-power wireless communication networks, for which the Long-Range (LoRa) is a rising star. Efficient network engineering requires the accurate prediction of the Received Signal Strength Indicator (RSSI) spatial distribution. However, the most commonly used models either lack the physical accurateness, resolution, or versatility for cityscape real-world building distribution-based RSSI predictions. For this purpose, we apply the 2D electric field wave-propagation Oscillator Finite-Difference Time-Domain (O-FDTD) method, using the complex dielectric permittivity to model reflection and absorption effects by concrete walls and the receiver sensitivity as the threshold to obtain a simulated coverage area in a 600 \u00d7 600 m2 square. Further, we report a simple and low-cost method to experimentally determine the signal coverage area based on mapping communication response-time delays. The simulations show a strong building influence on the RSSI, compared against the Free-Space Path (FSPL) model. We obtain a spatial overlap of 84% between the O-FDTD simulated and experimental signal coverage maps. Our proof-of-concept approach is thoroughly discussed compared to previous works, outlining error sources and possible future improvements. O-FDTD is demonstrated to be most promising for both indoors and outdoors applications and presents a powerful tool for IoT and smart city planners.<\/jats:p>","DOI":"10.3390\/s21082717","type":"journal-article","created":{"date-parts":[[2021,4,12]],"date-time":"2021-04-12T11:05:06Z","timestamp":1618225506000},"page":"2717","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Cityscape LoRa Signal Propagation Predicted and Tested Using Real-World Building-Data Based O-FDTD Simulations and Experimental Characterization"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9864-3922","authenticated-orcid":false,"given":"Ricardo M. R.","family":"Ad\u00e3o","sequence":"first","affiliation":[{"name":"Ultrafast Bio- and Nanophotonics Group, INL\u2014International Iberian Nanotechnology Laboratory, Av. Mestre Jos\u00e9 Veiga s\/n, 4715-330 Braga, Portugal"},{"name":"Campus de Ourense s\/n, Aerospace Engineering School, Universidade de Vigo, 32004 Ourense, Spain"}]},{"given":"Eduardo","family":"Balv\u00eds","sequence":"additional","affiliation":[{"name":"ERH-Illumnia, R. Feijoo 1, 32005 Ourense, Spain"}]},{"given":"Alicia V.","family":"Carpentier","sequence":"additional","affiliation":[{"name":"Defense University Center at the Spanish Naval Academy, University of Vigo, Plaza de Espa\u00f1a, S\/N, 36920 Mar\u00edn, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7854-7626","authenticated-orcid":false,"given":"Humberto","family":"Michinel","sequence":"additional","affiliation":[{"name":"Campus de Ourense s\/n, Aerospace Engineering School, Universidade de Vigo, 32004 Ourense, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4973-1889","authenticated-orcid":false,"given":"Jana B.","family":"Nieder","sequence":"additional","affiliation":[{"name":"Ultrafast Bio- and Nanophotonics Group, INL\u2014International Iberian Nanotechnology Laboratory, Av. Mestre Jos\u00e9 Veiga s\/n, 4715-330 Braga, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"60","DOI":"10.1109\/MWC.2016.7721743","article-title":"Long-range communications in unlicensed bands: The rising stars in the IoT and smart city scenarios","volume":"23","author":"Centenaro","year":"2016","journal-title":"IEEE Wirel. Commun."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"855","DOI":"10.1109\/COMST.2017.2652320","article-title":"Low Power Wide Area Networks: An Overview","volume":"19","author":"Raza","year":"2017","journal-title":"IEEE Commun. Surv. Tutor."},{"key":"ref_3","unstructured":"(2021, April 04). LoRa Alliance LoRaWAN 1.1 Specification 2017, 101. 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