Theory of Scalloping Amplitude Errors in Standard VOR Bearing Indications

A rigorous theory is developed for the course scalloping amplitudes observed in the bearing indications of an airborne standard VOR receiver in the presence of multipath signals. The VOR transmitting antenna pattern characteristics, the scattering properties of the multipath source, and the effects of ground reflection are all built into the theory so that their combined effects on the scalloping may be quantitatively investigated. The analysis assumes that the VOR receiver characteristics are ideal.