Performance Evaluation of Cognitive Radio Networks with a Finite Buffer Setting for Primary Users

Abstract

In this paper, in order to reduce possible packet loss of the primary users (PUs) in cognitive radio networks, we assume there is a buffer with a finite capacity for the PU packets. If a PU packet arrives during the transmission period of another PU packet, this newly arriving PU packet can initially access the PU buffer. In order to evaluate the influence of the buffer setting of the PU packets on the secondary users (SUs), we construct and analyze a discrete-time Markov chain model. Accordingly, we determine the expressions of some important performance measures of the PU packets and the SU packets, including the average queue length, the blocking rate, the throughput of PU packets and the average queue length, the interrupted rate, and the average delay of SU packets, respectively. Finally, we show numerical results to evaluate how the buffer setting of the PU packets influences the system performance of the PU packets and the SU packets.