On the teletraffic capacity of CDMA cellular networks

• Published in: IEEE transactions on vehicular technology 1999-01, Vol.48 (1), p.153-165
• Main Authors: Evans, J.S., Everitt, D.
• Format: Article
• Language: English
• Subjects: Applied sciences; Cellular; Cellular communication; Code division multiple access; Communication system traffic control; Distribution functions; Equipments and installations; Exact sciences and technology; Frequency; Interference; Land mobile radio cellular systems; Mathematical models; Mobile radiocommunication systems; Multiaccess communication; Networks; Performance analysis; Power control; Radiocommunications; Telecommunication traffic; Telecommunications; Telecommunications and information theory; Traffic control; Traffic engineering; Traffic flow
• ISSN: 0018-9545; 1939-9359
• DOI: 10.1109/25.740079

The aim of this paper is to contribute to the understanding of the teletraffic behavior of code-division multiple-access (CDMA) cellular networks. In particular, we examine a technique to assess the reverse link traffic capacity and its sensitivity to various propagation and system parameters. We begin by discussing methods of characterizing interference from other users in the network. These methods are extremely important in the development of the traffic models. We begin with a review of several existing approaches to the problem of handling other-cell interference before presenting a novel characterization of the interference in the form of an analytic expression for the interference distribution function in the deterministic propagation environment. We then look at extending the capacity analyses that assume a fixed and equal number of users in every cell to handle the random nature of call arrivals and departures. The simplest way to do this is by modeling each cell of the network as an independent M/G/x/spl infin/ queue. This allows us to replace the deterministic number of users in each cell by an independent Poisson random variable for each cell. The resulting compound Poisson sums have some very nice properties that allow us to calculate an outage probability by analyzing a single random sum. This leads to a very efficient technique for assessing the reverse link traffic capacity of CDMA cellular networks.