An Introduction to LTE: LTE, LTE-Advanced, SAE, VoLTE and 4G Mobile Communications, 2nd Edition

Chapter 18Enhancements in Release 9

At the time when the specifications for LTE Release 8 were being written, there was competition between LTE and WiMAX for support from network operators and equipment vendors. In view of this competition, 3GPP understandably wanted to finalize the specifications for Release 8 as soon as they could. To help achieve this, they delayed some of the peripheral features of the system until Release 9, which was frozen in December 2009.

This chapter covers the capabilities that were first introduced in Release 9, which include the multimedia broadcast/multicast service, location services and dual layer beamforming. The contents of Release 9 are described in the relevant 3GPP release summary [1] and there is a useful review in a regularly updated white paper by 4G Americas [2].

18.1 Multimedia Broadcast/Multicast Service

18.1.1 Introduction

Mobile cellular networks are normally used for one-to-one communication services such as phone calls and web browsing, but they can also be used for one-to-many services such as mobile television. There are two types of one-to-many service: broadcast services are available to anyone, while multicast services are only available to users who have subscribed to a multicast group. Broadcast and multicast services require several different techniques from traditional unicasting. For example, the network has to distribute the data using IP multicast, while the encryption techniques have to be modified to ensure that ...