MULTIPORT SCATTERING ANALYSIS OF GENERAL MULTILAYERED PRINTED ANTENNAS FED BY MULTIPLE FEED PORTS .1. THEORY

Part I of this paper describes a general solution to a class of printed antenna geometries composed of multiple dielectric layers or ground planes, radiating patches, dipoles, or slots, and an arbitrary configuration of multiple transmission lines proximity coupled or aperture coupled to the radiating elements. The solution uses a full-wave spectral-domain moment method approach, and a new generalized multiport scattering formulation to model the excitation from the multiple feed lines. This method treats infinite phased arrays as well as isolated elements. The general theory using the new multiport scattering formulation is elaborated, with details of the key analytical and numerical aspects. Considering the unified nature of the multiport scattering analysis, and its simplicity, this analysis is appropriate for computer simulation of a large variety of multilayered microstrip antennas involving radome layers, dual polarized feeds, proximity coupled or aperture coupled elements, multifeed stacked or parasitic patches, and several related configurations for integrated phased array applications. Part II of the paper will present application of the analysis to several specific geometries of interest.