Extended Delivery Time Analysis for Cognitive Packet Transmission with Application to Secondary Queuing Analysis

TL;DR

This paper analyzes the extended delivery time in cognitive radio systems, deriving exact distribution functions for secondary transmission delays under various sensing strategies and applying the results to secondary queuing analysis.

Contribution

It provides the first exact distribution functions for extended delivery time in cognitive radio, including continuous and periodic sensing, and applies these to secondary queuing delay analysis.

Findings

Exact distribution functions for extended delivery time derived.

Numerical and simulation results validate the mathematical model.

Closed-form expressions for expected delay in secondary queues obtained.

Abstract

Cognitive radio transceiver can opportunistically access the underutilized spectrum resource of primary systems for new wireless services. With interleave implementation, the secondary transmission may be interrupted by the primary user's transmission. To facilitate the delay analysis of such secondary transmission for a fixed-size secondary packet, we study the resulting extended delivery time that includes both transmission time and waiting time. In particular, we derive the exact distribution function of extended delivery time of secondary transmission for both continuous sensing and periodic sensing cases. Selected numerical and simulation results are presented for illustrating the mathematical formulation. Finally, we consider a generalized M/G/1 queue set-up at the secondary user and formulate the closed-form expressions for the expected delay with Poisson traffic. The analytical results will greatly facilitate the design of the secondary system for particular target application.