Diffraction over an infinitely wide plateau

The asymptotic path-integral technique is applied to radiowave propagation over an infinitely wide, perfectly conducting rectangular plateau for a ground-based transmitter and receiver. The total attenuation function can be resolved into two components: that due to the fields travelling over the plateau and that due to the fields interacting with the top of the plateau The resolution of fields into non-interacting and interacting components is a description which is not unique to, but arises naturally in the context of, path integration. The fraction of the total energy interacting with the top of the plateau is thus determined quantitatively and the theoretical predictions verified experimentally.