LASAR: Spectrum aware routing protocol for cognitive radio wireless networks

Cognitive radio technology is a new design paradigm for next-generation wireless networks which aims to provide dynamic utilization of the scarce radio spectrum. The cognitive radio technology enables temporary use of unused licensed spectrum by the secondary (unlicensed) users without causing interference to the primary (licensed) users thereby improving spectrum utilization. The dynamic spectrum access requires spectrum aware routing scheme which can sense the spectrum dynamically while calculating the new routes to the destination node. This work presents LASAR, a location aided spectrum aware routing protocol that allows users to exploit the geographic location information and discover the local spectrum access opportunities to improve the performance at each hop. The secondary user (SU) uses location information and channel usage characteristics to select the next hop relay from the available neighbor relays in the network. A novel routing metric is introduced which captures channel usage characteristics and location information in order to select the best route available to the destination node. The proposed routing protocol is simulated using event driven simulator (NS2) under cognitive radio scenario. The simulation results shows that the proposed routing protocol performs better under cognitive radio scenario and results in better end-to-end performance.