ABSTRACT
Cellular communication concepts are used in the design of modern cellular communication systems such as GSM, UMTS, WiMAX and LTE. In this chapter, some of the techniques which support efficient use of spectrum and network design are presented and explained. In general, the performance of a particular mobile communication system in terms of how well it uses available spectrum is quanitified in terms of the spectrum efficiency. A hexagon is usually assumed to be the shape of a cell theoretically. However, in practice the shape is amorphous due to the environmental impact on the signal propagation and also the technology in use such as the type of antenna applied at the base station and its location. In the downlink, mobiles at the cell edge experience larger degradation and interference compared to mobiles close to the base station, because by the time the transmitted signal reaches the edge of the cell, it has decayed significantly.
