Planning Factors and Their Influence on System Aspects

Introducing new or enhancing current radio services is dependent on the ability of the service to coexist with other services. Introduction of digital TV must also respect other services and international agreements concerning the use of spectrum. In some countries digital terrestrial TV will be introduced as enhancements of existing services, and new spectrum is not likely to be made available. This may even be true where the digital TV system is used for new services, because TV broadcasting is seen by many regulators as a spectrum inefficient service and because no free spectrum is available. As a consequence we have to face the fact that digital terrestrial TV must be able to coexist with present TV services in shared bands. This paper discusses the questions related to introduction of digital terrestrial TV, and in particular the possible trade-offs which will be necessary to make the service work. Will we accept a slightly reduced quality of the analogue service? What is the noise figure of new receivers? Should it be scalable? Can it be portable? What is the power range? Can it use adjacent channels? Other questions could be whether a worldwide scenario is possible. Are the constraints the same all over the world? Are the trade-offs equally acceptable anywhere? Yet another will be if one modulation scheme is superior to another, and must it carry HDTV from the start or would standard or enhanced definition do? There are questions about coverage, graceful degradation, service availability and so on. This paper deals with such problems as factors affecting the planning process.

Published

1994-01

Content type

Original Research

DOI

10.5594/M001283

ISBN

978-1-61482-945-4