查看文章

Cognitive radio is emerging as a promising technique to improve the utilization of the radio frequency spectrum in wireless networks. In this paper, we propose a hybrid CR (cognitive radio) system where underlay and overlay CR approaches are combined under SINR (Signal to Interference plus Noise Ratio) constraints. This new access type allows to optimize the spectrum sensing time with throughput improvement. The goal of this paper is to provide a new access mode in order to enhance the cognitive system performance while reducing the power spent for detecting the presence of the primary user and the spectrum holes. We consider the problem of spectrum sharing among primary (or “licensed”) users (PUs) and secondary (or “unlicensed”) users (SUs). In this scheme, the spectrum allocation problem is modeled as a non cooperative game, with each CR user acting as a player. Nash equilibrium is …