Chapter 19 - Rendezvous in Cognitive Radio Networks

Abstract

This chapter discusses the rendezvous in cognitive radio networks. Radio rendezvous for dynamic spectrum access (DSA) systems is still a largely open area for research. Much of the literature on multichannel communications simply assumes a common control channel (and, often, a radio dedicated to sensing and communicating over that control channel), thereby eliminating the rendezvous problem altogether. In the opportunistic access to spectrum, the use of a single control channel is not robust, as the appearance of an incumbent in that channel would be devastating to all communications among secondary users (SUs). This chapter outlines some approaches and points out their main pros and cons. Surely, as more DSA systems are deployed, opportunistically able to access an increasing number of channels, other competing approaches are suggested. Such approaches must be able to scale to a large number of channels and a large number of radios, achieving reasonable time-to-rendezvous (TTR) and high probability of rendezvous as long as at least one channel is currently available.