Investigation on Spectrum Sharing Technology Based On Cognitive Radio

Cognitive radio has received a lot of interests as a novel approach for improving the utilization of spectrum resource in recent years. In this paper, we first study the functional evolution of cognitive radio. Then following the discussion of the development of several spectrum policies and standardizations, we focus on the recent research issues of key techniques, such as spectrum sensing, primary user detection, dynamic spectrum allocation, power control, as well as the typical applications of cognitive radio in wireless region area network, ad hoc network and UWB system. We finish the discussion of our work by briefly investigating several possible future research directions of cognitive radio.