Romaszko, Sylwia (Institute for Networked Systems, RWTH Aachen University, Kackerstrasse 9, 52072 Aachen, Germany)
In Cognitive Radio Ad Hoc Networks (CRANs) a frequently changing environment and Primary Users (PUs) channel occupancy result in a need of the searching of common control channel (CCC) by Secondary Users (SUs) in order to be able to initiate a communication. A blind date or so-called rendezvous, required before an actual medium access, is therefore a new challenge, not encountered in single channel networks. Hence, new rendezvous protocols must be designed to handle this changeability of CCC in such a way that there is a guarantee that all nodes meet periodically in reasonable periods of time. Since pseudo-random solutions do not provide this guarantee, therefore, systematic approaches are needed, where, a.o., quorum systems (QSs) become popular, especially in power saving (PS) protocols. In this study, first we perform research on the element distribution in a period of a torus quorum system (tQS) in order to produce multiple quorums satisfying Rotation Closure Property in a single torus array. We also propose a novel distributed rendezvous (RDV) protocol for CRANs, tQS-RDV. We demonstrate that tQS-RDV guarantees RDV on at least two channels with a low number of available channels (r < 4), and on at least four channels otherwise.