Analysis Of Shaped Dielectric Lens Array Antenna By Modal expansion

Abstract

Theradiation pattern of Spheroidal dielectric lens excited by array antennais expressed in terms of spheroidal (SDL) modal expansion. Since the SDL Vector wave functions are not orthogonal, each the SDL modes are expressed in terms of aninfinite sum of Spherical (SPL) vector modes, that exhibit orthogonality over a measurement surface surrounding the lens and array. The spheroidal modal coefficients can be determined by applying boundary condition on the lens surface. Using the determined coefficients near fields on the measurement surface is computed. This field can be easily transformed to the far field using standard modal expansion. This technique has been applied to a 1x2 array at 10 GHz radiating into a SDL lens and the radiated fields computed with 20 SDL modes, with each SDL mode expressed as 20 SPL modes. The results are compared with a well-known EM flow solver.