A Cognitive Radio MAC protocol for exploiting bandwidth utilization in wireless networks

Cognitive Radio (CR) is a novel and promising spectrum management technique which aims to cope with the spectrum scarcity problem occurred in unlicensed bands and alleviate the inefficient spectrum utilization of licensed bands. To ensure that the operation of licensed users will not be adversely affected but the licensed bands can be fully utilized by the unlicensed users, this paper proposes a cognitive radio MAC protocol, called SMC-CR-MAC. When any Primary User (PU) is detected, the proposed SMC-CR-MAC applies Contiguous Channel Switching and Sender-Receiver Channel Swap approaches to cope with the rendezvous, packet collision, and channel congestion problems. Simulation results show that the proposed SMC-CR-MAC can significantly improve the network performance in terms of the utilization of licensed bands and network throughput.