Towards a more efficient spectrum usage: spectrum sensing and cognitive radio techniques

摘要: The traditional approach of dealing with spectrum management in wireless communications has been through the definition a licensed user granted exclusive exploitation rights for specific frequency. While interference is easily avoided, this unlikely to achieve objective maximizing value spectrum. In fact, measurements carried out worldwide have revealed significant underutilization. As result, so-called dynamic-spectrum-access networks (DSANs) are one current research trends area. such networks, unlicensed radios (secondary users) allowed operate bands provided that no harmful caused licensees (primary users). One key enabling technologies paradigm cognitive radio (CR). This envisages able sense and be aware its operational environment so as dynamically autonomously adjust parameters adapt different situations. Spectrum sensing, detection unused bands, then becomes elements cognitive-radio technologies. Within framework, on hand paper provides insight into spectrum-sensing techniques associated standardization activities. On other hand, also presents some spectrum-occupation measurement activities, targeting characterization how being used order extract relevant design. These presented from general methodological perspective, include results obtained particular case study.