Spectrum, Antennas and Propagation

This is the first of three chapters that discuss the underlying technologies that are used on the 5G air interface. After reviewing the use of radio spectrum by 5G, the chapter addresses the principles of antennas and antenna arrays, and considers the issues that affect radio propagation in a mobile telecommunication system, notably in the case of millimetre waves. The chapter also addresses issues that are important in a multipath environment, such as fading, coherence and channel reciprocity.