naa a22 4500 510794815 CHVBK 20180411083332.0 cr unu---uuuuu 180411e20130401xx s 000 0 eng 10.1007/s11277-012-0661-z doi (NATIONALLICENCE)springer-10.1007/s11277-012-0661-z Spatial Spectrum Reuse for Opportunistic Spectrum Access in Infrastructure-Based Systems [Elektronische Daten] [Dimitris Tsolkas, Nikos Passas, Lazaros Merakos] Opportunistic spectrum access (OSA) receives a constantly growing interest due to its potential to mitigate spectrum scarcity and meet the increasing communication needs of mobile users. OSA refers to identifying and exploiting spatiotemporal unused portions of licensed spectrum to allow communication among unlicensed-secondary users (SUs) without adverse impact to the licensees (primary users—PUs). Key parameters in OSA are the spectrum opportunities detection method used by the SUs, and the interference level perceived by the PUs. A spatial spectrum reuse framework is proposed, where broadcast messages of an infrastructure-based primary system are exploited and combined with location-aware methods to detect spectrum opportunities and establish interference-free secondary links. The study of secondary link establishment probabilities revealed a spectrum reuse of up to 25% for omni-directional and up to 90% for directional antennas. Moreover, increased throughput is achieved in both cases, with directional antennas attaining significantly better performance. Springer Science+Business Media, LLC., 2012 Cognitive radios nationallicence Opportunistic spectrum access nationallicence Spatial spectrum reuse nationallicence Uplink opportunities nationallicence Geometric analysis nationallicence Tsolkas Dimitris Department of Informatics and Telecommunications, University of Athens, 15701, Athens, Greece aut Passas Nikos Department of Informatics and Telecommunications, University of Athens, 15701, Athens, Greece aut Merakos Lazaros Department of Informatics and Telecommunications, University of Athens, 15701, Athens, Greece aut Wireless Personal Communications Springer US; http://www.springer-ny.com 69/4(2013-04-01), 1749-1772 0929-6212 69:4<1749 2013 69 11277 https://doi.org/10.1007/s11277-012-0661-z text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11277-012-0661-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Tsolkas Dimitris Department of Informatics and Telecommunications, University of Athens, 15701, Athens, Greece aut NATIONALLICENCE 700 1- Passas Nikos Department of Informatics and Telecommunications, University of Athens, 15701, Athens, Greece aut NATIONALLICENCE 700 1- Merakos Lazaros Department of Informatics and Telecommunications, University of Athens, 15701, Athens, Greece aut NATIONALLICENCE 773 0- Wireless Personal Communications Springer US; http://www.springer-ny.com 69/4(2013-04-01), 1749-1772 0929-6212 69:4<1749 2013 69 11277 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer