Distributed Cooperative Spectrum Sensing in Mixture of Large and Small Scale Fading Channels

作者：Reisi Nima^*; Gazor Saeed; Ahmadian Mahmoud

来源：IEEE Transactions on Wireless Communications, 2013, 12(11): 5406-5412.

DOI：10.1109/TWC.2013.092813.120549

• Cognitive radio
• cooperative spectrum sensing
• NP detector
• GLR detector
• ALR detector

In this paper, we study distributed energy detectors for spectrum sensing in cognitive radio networks. We treat the primary signal as unknown and deterministic with a known power and the channels as random with a Nakagami-Lognormal mixture distribution. In other words, the channel gains are modeled as product of two terms corresponding to the small and large-scale fadings. The small-scale terms are all Nakagami and independent for all sensors. Whereas for large-scale fading, sensors in each cluster are assumed to have identical Lognormal terms. We also assume that different clusters have independent large-scale fading. Assuming that the total energies from clusters are received, we investigate four distributed detection strategies: 1) Equal Gain Combining detector (EGCD), 2) Neyman-Pearson detector (NPD) or Likelihood Ratio detector (LRD) for known channel gains, 3) Generalized Likelihood Ratio detector (GLRD) for unknown gains, and 4) Average Likelihood Ratio detector (ALRD) given a priori distribution of channel gains. The simulation results show that the effects of both small and large-scale fadings on sensing performance should be considered simultaneously and confirm that a priori statistical information about large and small-scale fading used in ALRD result in performance improvement compared to EGCD and GLRD.

• 出版日期2013-11