Rendezvous in cognitive radio ad-hoc networks with asymmetric channel view

Abstract

Rendezvous in cognitive radio ad-hoc networks (CRAHNs) is a key step for a pair of unknown cognitive radio (CR) users to initiate communication. Channel hopping (CH) provides an effective method to guarantee rendezvous in CRAHNs. To design a CH scheme, assumption of symmetric channel information is widely used in the literature. This assumption may ease the CH design, but unable to capture the dynamic radio environment. To achieve the rendezvous in the shortest time, most of the existing CH sequences utilized the family of mathematical concepts such as prime number theory, Chinese remainder theory (CRT), quorum system and combinatorial block design and so on. However, rendezvous on a channel is rather influenced by the CR user preference on which it wants to achieve rendezvous. In this paper we address rendezvous problem with asymmetric channel information. This paper proposes an adaptive CH sequence based on local channel sensing information to achieve rendezvous in finite time and guarantees overlap on all available common channels. Results obtained show that variation in channel ranking has a significant influence on CH performance.