TABLE OF CONTENTS Ron Olexa
When designing a system or network, it is helpful (if not imperative) to know the coverage area provided by each site. This is important for two reasons: first, you want to assure that the users in the desired coverage area are served with a high quality signal, and second, you need to know how each transmitter adds to the interference levels in surrounding areas.
In order to evaluate the coverage that will be provided by the selected hardware, either propagation prediction models or physical surveys can be used. Propagation modeling is accomplished with a software tool, while physical surveys are accomplished by temporarily installing hardware then measuring the resulting coverage. If you are building few transmitter locations, or are only constructing systems inside buildings, the site survey may be the quickest and is certainly the most accurate method. If, on the other hand, you are planning multiple outdoor sites in various areas, the time and expense associated with acquiring and learning a software-based predictive model may prove valuable.
In the early 1980s, the first large scale cellular telephone networks began to be planned and constructed. In order to support these projects it was necessary to develop tools that would allow reasonably accurate prediction of RF propagation. Without such tools the only way to assess the coverage of a site was to perform a lengthy, complex and costly drive test on each site alternative. This involved erecting an antenna at the appropriate height (often 100...
