ABSTRACT

Due to the uncertainty in the available spectral resource, there is a need of inimitable challenges in cognitive radio networks. The most common decisive issue is that the performance degradation in cognitive radio ad-hoc networks (CRAHNs) experienced by cognitive users (CUs) due to the variation in the activity of primary users (PUs) in both frequency and space domain, diversity techniques can be represented an efficient way to address this issue. In this paper, we propose a link reliable joint path and spectrum diversity technique by modifying D2CARP with link quality metric such as CETX instead of hop count for effective use of spectrum in CRAHNs, is referred to as Link Reliable Dual Diversity Cognitive Ad-hoc Routing Protocol (LR-D2CARP). Make use of both link reliable path and spectrum diversities, CUs can switch dynamically to different link reliable paths as well as spectrum bands for communicating with each other in the presence of frequency- and space-varying PU activity. The simulation results reveal the effectiveness of our protocol in CRAHNs.

Keywords: - cognitive radio ad-hoc networks, link reliability, joint path, spectrum diversity, routing, QoS.