The diffraction of microwaves by buildings-a model for system planners

It is an increasing requirement for system planners to be able to predict the field strength in the shadow of a particular building. The most common building profile is that of a slab. Thus a signal in the shadow of such a building will have suffered double diffraction plus reflection on its path from the transmitter. Analytical methods are available to compute the diffracted field strength but these tend to be complex in nature and time consuming to implement. The author explains these analytical methods and shows comparisons between predictions made using such methods and the results of a measurement programme. He justifies the use of a new model which will allow rapid field strength predictions to be made. In addition methods by which the less onerous task of predicting the field strength in the shadow of a building of wedge profile are put forward