A Buffering and Switching Scheme for Admission Control in Cognitive Radio Networks.

Cognitive radio users (i.e., secondary users) experience a lot of performance degradation due to the continuous appearance of primary users in the cognitive radio networks. To minimize the effect of this phenomenon, we propose a buffering and switching scheme for admission control to enhance the performance of the secondary users. In the proposed scheme, the secondary users are competing for the available channels (i.e., licensed and unlicensed) with two different kinds of users and utilizing different kinds of buffers to reduce the blocking probability for newly arriving users and dropping probability for ongoing connection. The system is modeled using a multi-dimensional continuous-time Markov chain, where the performance metrics are obtained. The numerical results are verified using a discrete event simulations.