Edge diffraction of a narrow beam of millimeter waves in the shadow zone of an obstacle

Abstract

A mathematical description of the edge diffraction of a narrow beam of millimeter waves in the deep geometric shadow of an obstacle is proposed. The description uses the Babinet principle, according to which the complex amplitude of the diffracted field is determined as the difference of the complex amplitude of the radiation generated by an antenna in free space and the complex amplitude corresponding to the virtual radiation of the shadowing silhouette (obstacle) considered an aperture. The results of field experiments on diffraction of a beam of millimeter waves performed on a Luch telecommunications system are presented. The obtained experimental data completely confirm the effect of diffraction-induced amplification of a beam of millimeter waves in the shadow zone of an obstacle relative to the field of an omnidirectional (spherical) wave.