Cooperative spectrum sensing in cognitive radio networks based on maximizing channel capacity

摘要

Cognitive radio (CR) has been proposed to improve the spectrum efficiency. In this paper, we propose an optimal soft cooperation framework in order to gain higher spectrum efficiency. Within this framework, the original sensing information based on energy detection from CR users is sent to the data fusion center without any local processing. We make soft decisions on presence or absence of primary users and maximize channel capacity of the whole system at the same time. We prove that the optimal solutions can be converted into three conditions based on the first derivative of channel capacity with respect to false alarm probability. We further study how to set the optimal sensing settings to obtain the max channel capacity. Simulation results show a significant improvement of channel capacity by using the proposed strategies.