A GTD-based urban propagation model using building cover databases

Propagation modelling in an urban environment is required for microcellular network design, satellite-mobile coverage prediction, and the siting of small aperture terminals, amongst others. These applications require a full three-dimensional treatment of scattering and diffraction from the ground and buildings. The model must embrace not only the line-of-sight multipath situation, but also those cases where visibility is obstructed by buildings; at 900 MHz and 1.8 GHz the signal reaching a receiver by building diffraction may be comparable in strength to that reaching it by multiple reflection, or may be the only such signal. The assessment and modelling work described promises a flexible and adaptable approach to the problem of coverage prediction in the urban environment for microcell and satellite applications. A large number of measurements are already available against which to test the model