Chaotic oscillations in user-centric cognitive radio networks and their control

In the cognitive radio networks, spectrum resources are dynamically shared among the users for radio resource usage optimisation. However, depending on the distributed decision-making algorithms of the spectrum sharing procedure, undesirable chaotic switching may occur in the network. For chaotic non-linear systems, the chaos control theory has been proposed and applied to a wide variety of non-linear systems to stabilise such systems. In this paper, the delay feedback method for chaos control is applied to the chaotic phenomena in the cognitive radio networks. We show that our method can stabilise the chaotic oscillations in the user-centric cognitive radio networks. By comparisons with conventional parameter tuning methods, we confirm that our control approach is more efficient and faster to stabilise the cognitive radio systems.