{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,9]],"date-time":"2026-01-09T17:16:44Z","timestamp":1767979004298,"version":"3.49.0"},"reference-count":70,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,5,4]],"date-time":"2021-05-04T00:00:00Z","timestamp":1620086400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100011875","name":"Minist\u00e9rio da Ci\u00eancia, Tecnologia, Inova\u00e7\u00f5es e Comunica\u00e7\u00f5es","doi-asserted-by":"publisher","award":["01245.010604\/2020-14"],"award-info":[{"award-number":["01245.010604\/2020-14"]}],"id":[{"id":"10.13039\/501100011875","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The radio-frequency spectrum shortage, which is primarily caused by the fixed allocation policy, is one of the main bottlenecks to the deployment of existing wireless communication networks, and to the development of new ones. The dynamic spectrum access policy is foreseen as the solution to this problem, since it allows shared spectrum usage by primary licensed and secondary unlicensed networks. In order to turn this policy into reality, the secondary network must be capable of acquiring reliable, real-time information on available bands within the service area, which can be achieved by means of spectrum sensing, spectrum occupancy databases, or a combination of them. This Review presents guidelines related to the design of a framework that can be adopted to foster dynamic spectrum access policies. The framework applies special-purpose Internet of Things (IoT) devices that perform spectrum sensing, subsequently feeding a spectrum occupancy database, which in turn will be used by the secondary network to gather information on location-dependent spectrum availability. The guidelines address technological enablers capable of making the framework feasible, reliable and secure.<\/jats:p>","DOI":"10.3390\/s21093194","type":"journal-article","created":{"date-parts":[[2021,5,5]],"date-time":"2021-05-05T22:51:42Z","timestamp":1620255102000},"page":"3194","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Design Guidelines for Database-Driven Internet of Things-Enabled Dynamic Spectrum Access"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1304-792X","authenticated-orcid":false,"given":"Dayan A.","family":"Guimar\u00e3es","sequence":"first","affiliation":[{"name":"National Institute of Telecommunications (Inatel), S. R. Sapuca\u00ed 37540000, MG, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2420-5073","authenticated-orcid":false,"given":"Elivander J. T.","family":"Pereira","sequence":"additional","affiliation":[{"name":"National Institute of Telecommunications (Inatel), S. R. Sapuca\u00ed 37540000, MG, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0947-8575","authenticated-orcid":false,"given":"Ant\u00f4nio M.","family":"Alberti","sequence":"additional","affiliation":[{"name":"National Institute of Telecommunications (Inatel), S. R. Sapuca\u00ed 37540000, MG, Brazil"}]},{"given":"Jonas V.","family":"Moreira","sequence":"additional","affiliation":[{"name":"National Institute of Telecommunications (Inatel), S. R. Sapuca\u00ed 37540000, MG, Brazil"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1109\/MCOM.2014.6852082","article-title":"Cognitive radio in 5G: A perspective on energy-spectral efficiency trade-off","volume":"52","author":"Hong","year":"2014","journal-title":"IEEE Commun. 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