{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,20]],"date-time":"2026-04-20T20:15:59Z","timestamp":1776716159894,"version":"3.51.2"},"reference-count":54,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2021,12,16]],"date-time":"2021-12-16T00:00:00Z","timestamp":1639612800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministerio de Ciencia, Innovaci\u00f3n y Universidades, Gobierno de Espa\u00f1a","award":["RTI2018-095499-B-C31"],"award-info":[{"award-number":["RTI2018-095499-B-C31"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The densification of multiple wireless communication systems that coexist nowadays, as well as the 5G new generation cellular systems advent towards the millimeter wave (mmWave) frequency range, give rise to complex context-aware scenarios with high-node density heterogeneous networks. In this work, a radiofrequency electromagnetic field (RF-EMF) exposure assessment from an empirical and modeling approach for a large, complex indoor setting with high node density and traffic is presented. For that purpose, an intensive and comprehensive in-depth RF-EMF E-field characterization study is provided in a public library study case, considering dense personal mobile communications (5G FR2 @28 GHz) and wireless 802.11ay (@60 GHz) data access services on the mmWave frequency range. By means of an enhanced in-house deterministic 3D ray launching (3D-RL) simulation tool for RF-EMF exposure assessment, different complex heterogenous scenarios of high complexity are assessed in realistic operation conditions, considering different user distributions and densities. The use of directive antennas and MIMO beamforming techniques, as well as all the corresponding features in terms of radio wave propagation, such as the body shielding effect, dispersive material properties of obstacles, the impact of the distribution of scatterers and the associated electromagnetic propagation phenomena, are considered for simulation. Discussion regarding the contribution and impact of the coexistence of multiple heterogeneous networks and services is presented, verifying compliance with the current established international regulation limits with exposure levels far below the aforementioned limits. Finally, the proposed simulation technique is validated with a complete empirical campaign of measurements, showing good agreement. In consequence, the obtained datasets and simulation estimations, along with the proposed RF-EMF simulation tool, could be a reference approach for the design, deployment and exposure assessment of the current and future wireless communication technologies on the mmWave spectrum, where massive high-node density heterogeneous networks are expected.<\/jats:p>","DOI":"10.3390\/s21248419","type":"journal-article","created":{"date-parts":[[2021,12,16]],"date-time":"2021-12-16T21:32:40Z","timestamp":1639690360000},"page":"8419","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Towards Environmental RF-EMF Assessment of mmWave High-Node Density Complex Heterogeneous Environments"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7880-8224","authenticated-orcid":false,"given":"Mikel","family":"Celaya-Echarri","sequence":"first","affiliation":[{"name":"School of Engineering and Sciences, Tecnologico de Monterrey, Monterrey 64849, Mexico"}]},{"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, Monterrey 64849, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2693-5579","authenticated-orcid":false,"given":"Fidel Alejandro","family":"Rodr\u00edguez-Corbo","sequence":"additional","affiliation":[{"name":"School of Engineering and Sciences, Tecnologico de Monterrey, Monterrey 64849, Mexico"}]},{"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\/0000-0002-8776-4489","authenticated-orcid":false,"given":"Victoria","family":"Ramos","sequence":"additional","affiliation":[{"name":"Telemedicine and Digital Health Research Unit, Health Institute Carlos III, 28029 Madrid, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8263-1572","authenticated-orcid":false,"given":"Mohammad","family":"Alibakhshikenari","sequence":"additional","affiliation":[{"name":"Department of Signal Theory and Communications, Universidad Carlos III de Madrid, 28911 Legan\u00e9s, Madrid, Spain"}]},{"given":"Raed M.","family":"Shubair","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, New York University (NYU) Abu Dhabi, Abu Dhabi 129188, United Arab Emirates"}]},{"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"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,16]]},"reference":[{"key":"ref_1","unstructured":"(2021, May 24). 3GPP TR 38.913, Study on Scenarios and Requirements for Next Generation Access Technologies. 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