A new approach to 3-D ray tracing for a microcellular propagation prediction model in urban environments

This paper presents a new 3-D ray-tracing technique based on image theory. The proposed method can be applied to urban microcellular environments with arbitrary building layouts and heights. A new hybrid method combining the uniform geometrical theory of diffraction (UTD) with the near-field ray calculation method is also proposed in order to determine the diffraction loss due to propagation over buildings. Prediction results are in good agreement with measurements.