The Local Delay and the Throughput in Cooperative Cognitive Radio Ad Hoc Networks

Abstract

Cognitive radio ad hoc network is a framework which combines cognitive technique and ad hoc network. How to improve the performance of that network has always been a popular research for the past decades. In this paper, we study the local delay and the throughput in cooperative cognitive radio ad hoc networks. In order to forward the packets of primary users, a <inline-formula> <tex-math notation= LaTeX >$\\boldsymbol {\\tau }$ </tex-math></inline-formula>-slotted ALOHA protocol is adopted by secondary users in which a slot is divided into the first <inline-formula> <tex-math notation= LaTeX >$\\boldsymbol {\\tau }$ </tex-math></inline-formula>-slot and the latter <inline-formula> <tex-math notation= LaTeX >$\\left ({\\boldsymbol {1-\\tau }}\\right)$ </tex-math></inline-formula>-slot. By modeling the location of primary and secondary users as homogeneous Poisson point processes, we give the closed-form expression of the local delay and the throughput of both networks with two access strategies. Then, we optimize the two performance parameters with the intensity of secondary users. Numerical results show the feasibility of the optimal problem about the network performance metrics we proposed and could get an obvious better performance for primary users than that of ALOHA protocol by less sacrificing the performance of secondary users.