An algorithm towards QoS improvement of cognitive mobile users

Limited spectrum availability problem has become prevalent in the recent years. As solution, opportunistic spectrum access by the Cognitive Radio (CR) users is proposed. Networks supporting the CR users are called Cognitive Radio Networks (CRN). Introduction of CR users improves channel utilization (CU). However, channel allocation to the CR users without degradation of the Quality of Service (QoS) of the Primary Users (PU) is a significant problem. In this work, a Cognitive Channel Allocation Algorithm is proposed for a CRN where two homogeneous buffers have been considered. Continuous Time Markov Chain is used to model the system. It is observed that introduction of buffers improve the QoS of both handoff calls and new calls of the CR users. Improvement of over 12% in CU and about 40% in the call blocking probability has been observed which ensures satisfactory QoS of the CR users.