Introduction to mobile communications

Abstract

Mobile radio plays a very important role within the commercial, business and public safety sectors in almost all industrialized parts of the world. It is generally recognized as one of the most efficient ways to increase effectiveness, reduce operating costs and preserve energy. Growth has been rapid over the past few decades, and the provision of adequate radiofrequency spectrum to meet the increasing demand for licences is of primary concern to national radio regulatory administrations both in the long and short term. For many years, however, the continued demand for channels has not been matched by a corresponding increase in the amount of spectrum available. The allocation of a frequency band near 900 MHz for cellular mobile radio and the release of part of Band III (174-225 MHz) for trunked mobile radio systems in the UK has helped to ease the short-term problem, but there is evidence that even these bands will soon become congested, particularly in the major conurbations, and further action will be necessary.