Supporting Fast Rendezvous Guarantee by Randomized Quorum and Latin Square for Cognitive Radio Networks

Cognitive radio networks (CRNs) have been widely studied because they significantly enhance spectrum access efficiency. An essential issue for CRN communications is providing rendezvous between two nodes. An easy but impractical way to achieve rendezvous is to use a dedicated channel to exchange control messages. A better way to provide rendezvous is to exploit channel hopping. Most existing channel hopping solutions suffer from poor system performance. In this paper, we propose a novel distributed channel hopping protocol, i.e., randomized quorum and Latin square channel hopping (RQL). Utilizing the concepts of quorum systems, Latin squares, and a pseudorandom number generator, i.e., linear congruential generator (LCG), RQL efficiently provides rendezvous guarantee and balanced channel utilization. The concept of quorum systems is utilized to guarantee balanced rendezvous among nodes, whereas the concept of Latin squares and LCG is used to share the rendezvous among channels and to increase channel utilization, respectively. RQL is considered to be a flexible and robust solution that provides rendezvous guarantee for any pair of nodes in a CRN. Analytical and simulation results verify that RQL performs better in terms of time to rendezvous (TTR) and network throughput when comparing to existing rendezvous protocols, i.e., L-QCH, ACH, and QLCH.