A deterministic propagation model for the microcellular environment using multiple two-dimensional planes

Abstract

A simplified, computationally efficient radio-wave propagation model is proposed for the microcellular environment to calculate the path loss characteristics of the line-of-sight (LOS) and out-of-sight (OOS) paths in rural and urban environments. This method is based on ray-tracing through combined multiple two-dimensional (2D) planes and the use of a proposed non-reaching ray technique based on the uniform theory of diffraction and Fermat's principle. This paper is a generalization of the use of 2D plane models in the mobile environment. Rather than putting effort into predicting the environment, which is the usual practice, we lay emphasis on the way the ray could be traced towards the mobile in a predictive sense which would lead to reduced complexity of ray-tracing execution time without any serious loss of accuracy. We have utilized the predictive nature of reflections and diffractions to model the propagation paths in terms of multiple 2D planes. It is understood that while the rays follow only reflections, be it from buildings or ground, they will traverse in a well defined plane for a given receiver's position. The same is true for diffraction also. Multiple image theory is used to simplify the ray paths for computation. Rural and urban environments are considered as streets of LOS and OOS paths. Path loss characteristics are determined as a function of polarization, base station antenna height and the diffracted field component. Validation of the theoretical curves is achieved by the experimental results to confirm the efficiency of the proposed model.