Antenna mismatch induced by nearby scatterers through a spherical wave - Generalized scattering matrix approach

This paper presents a procedure based on a spherical wave (SW) formalism for the estimate of the perturbations induced on the input impedance of an antenna by a nearby obstacle like a reflector. The antenna is characterized by using the total scattering matrix; the scattering from the obstacle is studied through a physical optics approach, and the interaction between the two objects is described in terms of radiated spherical waves (SW). The main advantages of the proposed technique are simplicity, direct interfaceability with the output of measurement procedures and moderate computational cost.