Performance Analysis of Cognitive Radio Networks against Secondary User´s Policies

In a cognitive radio network (CRN), instead of direct leaving, an interrupted secondary user (SU) is suspended to wait for another channel. The policy for the packets generated by the SU during the suspending time can be either discarding or buffering. This paper mainly analyzes the performance of a CRN against these two policies. Here, two Markov models are proposed to derive the formulas for packet loss ratio, packet delay and spectrum utilization. Numerical results show that theoretical models are consistent with simulation results. The major observations include (i) The performance of a CRN is more sensitive to the primary userspsila traffic loads than that of secondary users and (ii) adopting discarding or buffering policy for the packets of SUs does not make much difference to the CRNpsilas spectrum utilization.