{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,7]],"date-time":"2025-11-07T09:43:45Z","timestamp":1762508625199,"version":"build-2065373602"},"reference-count":26,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2021,10,9]],"date-time":"2021-10-09T00:00:00Z","timestamp":1633737600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003141","name":"Consejo Nacional de Ciencia y Tecnolog\u00eda","doi-asserted-by":"publisher","award":["Student scholarship number 746015"],"award-info":[{"award-number":["Student scholarship number 746015"]}],"id":[{"id":"10.13039\/501100003141","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Chilean Research Agency ANID","award":["ANID FONDECYT 1211368 and ANID PIA\/APOYO AFB180002"],"award-info":[{"award-number":["ANID FONDECYT 1211368 and ANID PIA\/APOYO AFB180002"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Deep knowledge of how radio waves behave in a practical wireless channel is required for the effective planning and deployment of radio access networks in outdoor-to-indoor (O2I) environments. Using more than 400 non-line-of-sight (NLOS) radio measurements at 3.5 GHz, this study analyzes and validates a novel O2I measurement-based path loss prediction narrowband model that characterizes and estimates shadowing through Kriging techniques. The prediction results of the developed model are compared with those of the most traditional assumption of slow fading as a random variable: COST231, WINNER+, ITU-R, 3GPP urban microcell O2I models and field measured data. The results showed and guaranteed that the predicted path loss accuracy, expressed in terms of the mean error, standard deviation and root mean square error (RMSE) was significantly better with the proposed model; it considerably decreased the average error for both scenarios under evaluation.<\/jats:p>","DOI":"10.3390\/s21206716","type":"journal-article","created":{"date-parts":[[2021,10,10]],"date-time":"2021-10-10T21:37:49Z","timestamp":1633901869000},"page":"6716","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Testing a 5G Communication System: Kriging-Aided O2I Path Loss Modeling Based on 3.5 GHz Measurement Analysis"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8215-3593","authenticated-orcid":false,"given":"Melissa Eugenia","family":"Diago-Mosquera","sequence":"first","affiliation":[{"name":"Escuela de Ingenier\u00eda y Ciencias, Tecnologico de Monterrey, Av. Epigmenio Gonz\u00e1lez 500, Fracc. San Pablo, Quer\u00e9taro 76130, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3098-7275","authenticated-orcid":false,"given":"Alejandro","family":"Arag\u00f3n-Zavala","sequence":"additional","affiliation":[{"name":"Escuela de Ingenier\u00eda y Ciencias, Tecnologico de Monterrey, Av. Epigmenio Gonz\u00e1lez 500, Fracc. San Pablo, Quer\u00e9taro 76130, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1235-8566","authenticated-orcid":false,"given":"Mauricio","family":"Rodriguez","sequence":"additional","affiliation":[{"name":"Escuela de Ingenier\u00eda El\u00e9ctrica, Pontificia Universidad Cat\u00f3lica de Valpara\u00edso, Valpara\u00edso 2362804, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,9]]},"reference":[{"key":"ref_1","unstructured":"Small Cell Forum (2020). 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[4th ed.].","DOI":"10.1007\/978-3-662-46244-7_7"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/20\/6716\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T07:11:09Z","timestamp":1760166669000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/20\/6716"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,10,9]]},"references-count":26,"journal-issue":{"issue":"20","published-online":{"date-parts":[[2021,10]]}},"alternative-id":["s21206716"],"URL":"https:\/\/doi.org\/10.3390\/s21206716","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2021,10,9]]}}}