摘要

Spectrum access and assignment in cognitive radio networks (CRNs) are hot topics in wireless communications. Dynamic spectrum access and assignment could greatly improve spectrum resource efficiency and help to satisfy the explosively increasing communication demands of wireless devices. The problem of spectrum access and assignment in an underlay CRN is considered in this paper. The problem is modeled as a global optimization problem by considering the interference between primary and secondary users, the interference between secondary users and the utilization of the entire network. The utilization of the underlay CRN is maximized in the optimization model. To effectively solve this combinatorial optimization problem, a modified binary artificial bee colony algorithm is proposed. Numerical experiments are conducted to simulate the network and verify the proposed assignment method. The simulation results show that the proposed assignment method offers good performance in improving the spectrum usage efficiency and reducing the interference among primary and secondary users. Furthermore, the proposed algorithm is also very effective in achieving optimal allocation solutions compared with other methods.