Study On Spectrum Sensing of Cognitive Radio Networks

• Main Authors: Chih-Wei, Chen, 陳治瑋
• Other Authors: Yaw-Wen, Kuo
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/94090134288066712055

碩士 === 國立暨南國際大學 === 電機工程學系 === 100 === Cognitive radio is an important technology of Cognitive Networks, which solves the issues of spectrum scarcity and spectrum under-utilization. In order to mitigate the channel variation and to improve the detection probability, Cooperative Spectrum Sensing(CSS) has been proposed. The Fusion Rule is the main part of CSS. Because some commonly used fusion rules (such as AND Rule, OR Rule, Majority Rule) belong to the category of n out of K Rule, this thesis focuses on n out of K Rule. In addition, we also investigate the Optimal Rule which is based on the likelihood ratio test. For the scenario of equal SNR betweens Secondary users (SUs), we find that actually the Optimal Rule is equivalent to the n out of K Rule only if we set the threshold properly for the Optimal Rule. Only when the SUs’ SNRs are different, the Optimal Rule performs better. The performance difference becomes significant when the variation of SNR is large.