Abstract: In cognitive radio networks, cooperative spectrum sensing can improve spectrum sensing detection performance by using multiple nodes sensing simultaneously. However, with the increase of the number of secondary users (SU), energy consumption increases and energy efficiency (EE) decreases. In order to solve this problem, an energy efficiency model based on hybrid spectrum sharing mode is constructed by combining two sharing modes of opportunistic spectrum access and underlay spectrum sharing. Meanwhile, three different fusion rules, reoccupation probability of primary user (PU) and reporting channel error are considered. Aiming at maximizing EE of the secondary system, Lagrange multiplier method and sub gradient descent algorithm are used for sensing time, the number of participants and the transmission power of users to be solved by iterative optimization. The simulation results show that the algorithm can achieve higher throughput and energy efficiency under the constraints of the minimum quality of service (QoS) and transmission power.

Key words: cognitive radio network, energy efficiency, cooperative spectrum sensing, hybrid spectrum sharing, power allocation