Resource Allocation in Multi‐Tier Networks with Cognitive Small Cells

The resource allocation in a multi‐tier network and the network performance are closely related to the off‐loading technique used to divide the traffic load among the different network tiers. This chapter discusses how to evaluate the share that each network tier serves from the complete set of users and how to optimize the design parameters to off‐load users from one network tier to another. Off‐loading users to the small cells has two merits, one from the access network and the other from the core network point of view. The chapter analyzes the off‐loading efficiency for three off‐loading techniques in a two‐tier network: off‐loading via power control, off‐loading via increasing the intensity of SBSs, and off‐loading via biasing. Recently, stochastic geometry has been used to model and analyze multi‐tier cellular networks. The chapter discusses the basics of the stochastic geometry‐based modeling in the context of cellular wireless networks.