Queueing Analysis for Preemptive Transmission in Underlay Cognitive Radio Networks

TL;DR

This paper analyzes preemptive queueing in underlay cognitive radio networks, focusing on high-priority impatient packets, and provides insights into system performance and parameter optimization.

Contribution

It introduces a queueing model for heterogeneous packets with preemption and impatience, analyzing reneging probability and waiting times in underlay CR networks.

Findings

High priority packet waiting time decreases with interference threshold.

Low priority packet waiting time is proportional to high priority arrival rate.

Model helps in designing efficient MAC protocols.

Abstract

In many cognitive radio applications, there are multiple types of message queues. Existing queueing analysis works in underlay CR networks failed to discuss packets heterogeneity. Therefore high priority packets with impatient waiting time that have preemptive transmission opportunities over low class are investigated. We model the system behavior as a M/M/1+GI queue which is represented by a two dimensional state transition graph. The reneging probability of high priority packets and the average waiting time in two-class priority queues is analyzed. Simulation results demonstrate that the average waiting time of high priority packets decreases with the growing interference power threshold and the average waiting time of the low priority packet is proportional to the arrival rate of the high priority packet. This work may lay the foundation to design efficient MAC protocols and optimize long term system performance by carefully choosing system parameters.