Performance of secondary user in Opportunistic Spectrum Access System

Opportunistic Spectrum Access (OSA) has been proposed as a promising solution to the spectrum scarcity problem. OSA network not only respects the rights of incumbent license holders but also takes care of the Quality of Service (QoS) of secondary users. In this paper, a multichannel preemptive priority queuing model is developed and a buffer is introduced to reduce the force termination probability and blocking probability of secondary users. Mathematical approach was presented to study the secondary system performance in terms of communication time, which is the time interval between secondary user´s arrival and departure, including waiting and transmission time.