Full-Wave Analysis of Scattering from a Stub Loaded Micro strip Patch Antenna

Abstract

The design of a microstrip reflectarray requires precise prediction of the phase and amplitude of the field scattered by either an unloaded patch or a stub-loaded patch. In this paper, we present a full-wave formulation, using sub-domain expansion functions and spectral-domain Green’s functions, for a rectangular patch loaded with a T-shaped stub. The formulation is general in the sense that it can be used to analyze an unloaded patch and a patch loaded with either a linear or L-shaped or T-shaped stub. Numerical results on the radar cross-section (RCS) are presented for various geometries as a function of frequency and angles of incidence. The effect of various parameters, such as, dielectric constant, substrate thickness, on the scattering properties of the patch is also discussed.