Investigation of a new quasi-optical waveguide modeling method for backward and forward scattering study in millimeter and submillimeter wave bands

In the method, the object under investigation is situated in a quasi-optical waveguide structure which presents a circular hollow dielectric waveguide (HDW) and the main waveguide mode, HE₁₁, scattering parameters are determined. The parameters are related to the object under investigation obtaining RCS in a quite definite manner. The HDW presents a remarkable combination of useful properties because it is a guiding, forming and filtering quasi-optical structure that allows one to place sufficiently large (as compared with wavelength) nonuniformities in its waveguide channel. Owing to the properties, in conjunction with HE₁₁ mode field quasi-plane character and some other HDW merits, it turned out to be possible to simulate the conditions for electromagnetic wave scattering by an object placed in a certain region inside the HDW that is close to the conditions existing when a uniform plane wave is scattered by the same object placed in free space. Therefore, HDW plays in the QWM method the role of the main component of a micro-compact range intended for the study of scattering characteristics of various physical objects under laboratory conditions in the short millimeter and submillimeter wave bands