Spherical modal analysis of shaped dielectric lens antennas for mobile broadband applications (MBS)

In this paper an accurate analytical formulation based on spherical modal expansion (SME) of the near fields of small apertures radiating in the presence of a shaped dielectric lens is presented. The analysis treats the lens as a scatterer. It utilizes techniques for radial translation and coordinate rotation of the small aperture spherical modal coefficients to align them to the phase center of the dielectric lens. The SME coefficients of the scattered fields due to the lens are then obtained by application of boundary conditions. A sample computation is performed to demonstrate the approach and supported by an experimental result. The analysis is flexible enough to accommodate different types of radiating apertures and different shapes for the dielectric lenses.