Division Significant heights above the ground

The equivalent heights are obtained from the mean ground plane between the source and the receiver. This replaces the actual ground with a fictitious plane representing the mean profile of the land.

The equivalent height of a point is its orthogonal height in relation to the mean ground plane. The equivalent source height z_s and the equivalent receiver height z_r can therefore be defined. The distance between the source and receiver in projection over the mean ground plane is noted by d_p .

If the equivalent height of a point becomes negative, i.e. if the point is located below the mean ground plane, a null height is retained, and the equivalent point is then identical with its possible image.