EFFICIENT DISCOVERY OF SPECTRUM OPPORTUNITIES VIA ADAPTIVE COLLABORATIVE SPECTRUM SENSING IN COGNITIVE RADIO NETWORKS

In this paper, we construct a novel MAC-layer sensing framework for fast discovery of spectrum opportunities. We employ the sequential probability ratio test and a novel collaborative sensing scheme, in which the collaboration exists among multiuser and multi-slot. Then, we propose a novel scheme of adaptive collaboration sensing schedule for fast spectrum opportunities discovery and prove that the sensing order based on sorting is optimal with respect to fast discovery. Moreover, we formulate the adaptive collaboration as an optimization problem, which, however, is an NP-hard problem. Then, we give a suboptimal solution to the problem with low complexity. Simulation results show that the proposed scheme could fast discover the spectrum opportunities.