Abstract
Cognitive Radio (CR) technology is an emerging and promising technology which enables the temporary use of the unused licensed spectrum without interfering with the transmissions of other users, thereby improving spectrum utilization. The spectrum is dynamically reused by the alteration of its power, frequency, modulation, and other operating parameters after sensing its radio frequency environment. Cognitive Radio Ad hoc Networks (CRAHNs) are ad hoc networks with CR capability. Routing is a critical issue in CRAHNs which has to be addressed, as the mechanism to form routes in the classical ad hoc networks is completely different from CRAHNs. This paper provides three main contributions. First, NS-2 has been extended to address CR routing by providing multi radio and multi-channel support. Secondly, the extended NS-2 provides a base for realistic simulation and performance evaluation of CR routing algorithms. Finally, in this paper, we have proposed a Routing Protocol for Cognitive Radio Ad hoc Network (RPCRAN) which considers CR users activity in CRAHNs. Evaluation of the proposed protocol has been compared against AODV under the extended NS-2 cognitive environment. Simulation results show our proposed protocol performs better.