A UTD-based propagation model for cellular mobile radio systems

This work develops a UTD-based propagation model from some existing models. The model calculates the total path loss caused by free space, by buildings in the vicinity of the mobile and by multiple diffractions due to buildings for cellular mobile radio propagation. As a major contribution, a more closed expression for multiple diffractions caused by rows of buildings is derived and analysed. This improved expression is more appropriate not only for numerical calculation but also for theoretical analysis. As some developments, the loss caused by the local row of buildings, together with that due to free space, is derived and explicitly expressed. The existing models predicted the path loss for the vertically polarized electric field. As a theoretical extension, the present work predicts the path loss for the horizontally polarized electric field as well. Numerical results at 1-30 GHz are presented and studied. When the horizontal range between the mobile and buildings is less than 20 meters, the total path loss for the horizontally polarized electric field is considerably larger than that for the vertically polarized electric field. It is predicted that the polarization dependence becomes less important once the horizontal range between the mobile and buildings is beyond a few tens of meters.