Abstract:

The cognitive radio network is proposed in the face of scarce spectrum resources

and a variety of heterogeneous wireless access techniques. Media Access Control (MAC)

protocol decides how the nodes in the networks receive and send data by shared wireless

channels. Whether the MAC protocol can use the limited channel effectively or not plays a

very important role in the performance of the cognitive radio network. Focusing on designing

and implementing an excellent MAC protocol in cognitive radio networks, CRMMAC is

proposed, which is an improved MAC protocol based on MMAC. In CRMMAC, there is a dedicated

control channel. The network conditions, channel usage model, protocol frame structure and

channel access strategy are presented. The simulation result shows that the proposed

protocol has good performance.

Key words: cognitive radio networks;media access control protocol;spectrum sense;channel access