MAC and Routing Protocols for AD-HOC Cognitive Radio Networks

Cognitive radio network is a new emerging research area recently. It enhances the existing software-defined radio [1], whose physical layer behaviour is largely defined in software. Cognitive radio has the following characteristics [2]. First, it is aware of its environment and its capabilities. Second, it is able to independently alter its physical layer behaviour based on its previous experience and its current environment. When spectrum environment changes around cognitive user, it is capable of sensing these changes and independently changing its physical layer settings such as transmission power, channel selection and etc to meet some constraints or QOS requirements of the users. In this paper, NS-2 is used to extend it to support cognitive radio network simulation with single radio multichannel and the improved MAC provides efficient spectrum utilisation. And the performance metric is evaluated using AODV routing protocol.