A Cognitive Radio Network Architecture without Control Channel

The spectrum-agile cognitive radio has been developed to significantly increase spectrum utilization and relieve the spectrum exhaustion problem, by enabling secondary users to dynamically access the licensed spectrum bands. As such cognitive radio will be a key feature of future wireless technologies. In this paper, we propose an architecture for cognitive radio network (CRN). Our architecture uses one radio per node and does not need a common control channel, and is highly adaptable and resilient to maintain connectivity between neighboring nodes. In particular, we present a channel selection algorithm that not only spreads nodes into different channels to reduce cochannel interference, but also enables a node to easily compute the channel of a neighbor without the need to negotiate with the neighbor, which is highly desirable for CRN, as a channel may become inaccessible abruptly due to that the licensed user suddenly starts using it. Simulation results show that our CRN model and channel selection algorithm are highly adaptable and resilient to dynamic channels, and can achieve a close performance to the scheme that uses an extra radio and a static control channel to exchange channel information.