Heterogeneous Cellular Networks

11

Distributed Location Management for Generalized HetNets. Case Study of All-wireless Networks of Femtocells

Josep Mangues-Bafalluy, Jaime Ferragut and Manuel Requena-Esteso

Centre Tecnològic de Telecomunicacions de Catalunya, Spain

11.1 Introduction

The increase of capacity offered by wireless networks is closely associated with the reduction of cell radii. In fact, as pointed out in [1], out of a million-fold capacity increase since 1957, a 1600× factor of system capacity improvements is due to reduced cell sizes. Much less important are other factors, such as the availability of wider spectrum or better modulation schemes. This is highly relevant in a context in which the growth of mobile broadband traffic is starting to stress access and backhaul networks of mobile network operators (MNOs). This is one of the main driving forces behind heterogeneous cellular networks (HetNets). In the 3GPP vision, HetNets combine MNO-deployed cells (e.g., macrocells, microcells) with short-range, subscriber-deployed nodes (e.g., femtocells), but it is assumed that they all use 3GPP access technologies (e.g., LTE), and depending on the scenario, even the same technology [3].

In this chapter, we extend/generalize the HetNet vision along various lines. First, we consider diverse wireless technologies, including non-3GPP ones (e.g., WiFi). Second, we study the implications of HetNet deployments, not just at the radio resource management level, as usually done, but also at the architectural level. ...