Chapter 27
Introduction to LTE-Advanced
27.1 Introduction and Requirements
With the completion of LTE Release 8, 3GPP started to look into ways to further evolve LTE for the future, in order to build upon the existing LTE technology and to ensure that LTE remains the leading global standard for mobile broadband.
Enhanced performance can in principle be achieved in two ways – by using more radio spectrum, and by using the available spectrum more efficiently. The International Telecommunication Union (ITU) has taken steps to ensure that more radio spectrum will be available, globally whenever possible, for systems beyond the 3rd Generation. The World Radiocommunication Conference (WRC) 2007 resulted in some new spectrum bands being earmarked for mobile services. In order to satisfy the perceived needs and to ensure that effective use is made of spectrum allocations, in March 2008 the ITU Radiocommunication Sector (ITU-R) issued a ‘circular letter’ [1] calling for submission of candidate Radio Interface Technologies (RITs). Successful proposals would fulfil the ITU-R’s requirements for IMT-Advanced1 [2].
Key features of IMT-Advanced set out in the circular letter are:
- A high degree of commonality of functionality worldwide, while retaining the flexibility to support a wide range of services and applications in a cost-efficient manner;
- Compatibility of services within IMT and with fixed networks;
- Capability of interworking with other radio access systems;
- High ...