Introduction

Abstract

Once upon a time, cellular wireless networks provided two basic services: voice telephony and low-rate text messaging. Users in the network were separated by orthogonal multiple access schemes, and cells by generous frequency reuse patterns [1]. Since then, the proliferation of wireless services, fierce competition, and the emergence of new service classes such as wireless data and multimedia have resulted in an ever increasing pressure on network operators to use resources in a more efficient manner. In the context of wireless networks, two of the most common resources are power and spectrum—and, due to regulations, these resources are typically scarce. Hence, in contrast to wired networks, overprovisioning is not feasible in wireless networks.