A novel spectrum-aware routing protocol for multi-hop cognitive radio ad hoc networks

Cognitive radio (CR) technology is a new communication paradigm that can be a solution to the spectrum scarcity problem. The new spectrum usage pattern necessitates corresponding routing protocols to exploit the available spectrum opportunistically. In this paper, we propose a novel Spectrum-Aware Routing Protocol (SARP) for multi-hop cognitive radio ad hoc networks. SARP integrates channel choice with route discovery to cope with dynamic spectrum by considering the actions of PUs. In addition, a local route maintenance and recovery mechanism is presented to deal with sudden appearance of PUs. Rerouting probability and channel usage ratio are introduced to evaluate the performance of this routing protocol. Simulation results show that the proposed scheme reduces rerouting probability obviously and increases channel usage ratio of SUs significantly.