{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,6]],"date-time":"2026-02-06T00:46:29Z","timestamp":1770338789628,"version":"3.49.0"},"reference-count":24,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2017,3,27]],"date-time":"2017-03-27T00:00:00Z","timestamp":1490572800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Research Foundation of Korea (NRF)","award":["NRF-2015R1A2A2A03004152"],"award-info":[{"award-number":["NRF-2015R1A2A2A03004152"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper investigates the impact of using directional antennas and beamforming schemes on the connectivity of cognitive radio ad hoc networks (CRAHNs). Specifically, considering that secondary users use two kinds of directional antennas, i.e., uniform linear array (ULA) and uniform circular array (UCA) antennas, and two different beamforming schemes, i.e., randomized beamforming and center-directed to communicate with each other, we study the connectivity of all combination pairs of directional antennas and beamforming schemes and compare their performances to those of omnidirectional antennas. The results obtained in this paper show that, compared with omnidirectional transmission, beamforming transmission only benefits the connectivity when the density of secondary user is moderate. Moreover, the combination of UCA and randomized beamforming scheme gives the highest path connectivity in all evaluating scenarios. Finally, the number of antenna elements and degree of path loss greatly affect path connectivity in CRAHNs.<\/jats:p>","DOI":"10.3390\/s17040690","type":"journal-article","created":{"date-parts":[[2017,3,27]],"date-time":"2017-03-27T10:49:10Z","timestamp":1490611750000},"page":"690","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Impact of Beamforming on the Path Connectivity in Cognitive Radio Ad Hoc Networks"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7297-7705","authenticated-orcid":false,"given":"Le","family":"Dung","sequence":"first","affiliation":[{"name":"Department of Radio and Communication Engineering, Chungbuk National University, Cheongju City, Chungbuk 28644, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6328-3103","authenticated-orcid":false,"given":"Tran","family":"Hieu","sequence":"additional","affiliation":[{"name":"Department of Electronics and Computer Engineering in Graduate School, Hongik University, Sejong City 30016, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Seong-Gon","family":"Choi","sequence":"additional","affiliation":[{"name":"Department of Radio and Communication Engineering, Chungbuk National University, Cheongju City, Chungbuk 28644, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9824-1950","authenticated-orcid":false,"given":"Byung-Seo","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Computer and Information Communication Engineering, Hongik University, Sejong City 30016, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Beongku","family":"An","sequence":"additional","affiliation":[{"name":"Department of Computer and Information Communication Engineering, Hongik University, Sejong City 30016, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,3,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"810","DOI":"10.1016\/j.adhoc.2009.01.001","article-title":"CRAHNs: Cognitive radio ad hoc networks","volume":"7","author":"Akyildiz","year":"2009","journal-title":"Ad Hoc Netw."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"432","DOI":"10.1093\/comjnl\/47.4.432","article-title":"On the Connectivity of Ad Hoc Networks","volume":"47","author":"Bettstetter","year":"2004","journal-title":"Comput. 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