Control channel etiquettes: implementation and evaluation of a hybrid approach for cognitive radio networks

Cognitive Radio (CR) has emerged as the promising technology to address spectrum scarcity issues. One of the challenging tasks in CR networks is to agree on a common control channel to advertise the free channel list (FCL) amongst the participating CR nodes for co-operative communication. In this paper, a CR MAC protocol for searching, scanning, and accessing the control channel is proposed. The protocol consists of two levels of selection: rapid channel accessing and reliable channel accessing. In rapid channel accessing, nodes quickly and efficiently converge to a newly found control channel. In reliable channel accessing, switching to the backup control channel is performed whenever there is a PU claim on licensed channel. Furthermore, our reliable channel accessing allows CR nodes to access more than one control channel simultaneously. We evaluate the performance of the proposed approach through simulation modelling. The results show that our protocol can achieve efficient channel access time and fairness.