Delay analysis of the Go-Back-N ARQ protocol over a time-varying channel

Abstract

In this paper we present an analytical technique, based on the use of probability generating functions, to analyze the throughput performance and the transmitter buffer behavior of a Go-Back-N ARQ system, with the notable complication that the errors in the channel are correlated in time. We model the transmitter buffer as a discrete-time queue with infinite storage capacity and independent and identically distributed packet arrivals. Arriving packets are stored in the queue until they are successfully transmitted over the channel. The probability of an erroneous transmission is modulated by a general Markov chain with M states, rather than assuming stationary channel errors. We find explicit expressions for the probability generating functions of the buffer content and packet delay. From these functions moments and tail probabilities can be derived. Numerical results illustrate the impact of the error process on the system performance. © Springer-Verlag Berlin Heidelberg 2005.