Modelling of radiowave propagation in urban environment

The parabolic equation (PE) method is a fast and powerful technique which allows accurate modelling of radiowave diffraction and scattering from buildings, including detailed features like doors, windows, wall roughness, etc. It is important, particularly at high frequencies, to predict the effects of these features on the scattered field structure, saving measurement costs. The PE method is most effective for small scale problems like scattering from a single building or a group of buildings. The detailed information obtained in this way can be used with ray-tracing codes to predict propagation over large areas. We present results on scattering from buildings with different features (doors, windows with metal frames, etc.), scattering from a rough brick wall and propagation along a street. The simulations were compared with experimental data, and very good agreement was found. A particularly interesting result is obtained for scattering from a rough brick building at millimetre frequencies (38 GHz), where the scattered field has sharp peaks in the specular region. The results show the typical behaviour of the scattered field at high frequencies. This provides useful information for the planning of urban communication systems