Distributed Mechanisms for Multiple Channel Acquisition in a System of Uncoordinated Cognitive Radio Networks

Due to the constraint imposed by the Dynamic Spectrum Access paradigm, Cognitive Radio (CR) networks are entangled in persistent competition for opportunistic access to underutilized spectrum resources. In order to maintain quality of service, each network faces the challenge of acquiring dynamic enough channels to meet channel size requirement. The main goal of every CR network is to minimize the amount of contention experienced during channel acquisition and to maximize the utility derived from acquired channels. This is a major challenge, especially without a global communication protocol that can facilitate communication between the networks. This chapter discusses self-coexistence of CR networks in a decentralized system with no support for coordinated radio transmission activities. Channel acquisition mechanisms that can help networks minimize contention and maximize utility are also discussed. The mechanisms guarantee fast convergence of the system leading to an equilibrium state whereby networks are able to operate on acquired channel with minimal or zero contention.