Efficient Full-Wave Analysis of Lens Antennas With Arbitrary Feeder

The full-wave response of lenses with symmetry of revolution and arbitrary feeder, including mutual coupling, is efficiently obtained. For this purpose, a domain decomposition is carried out using concave or convex spherical ports, and the finite element method (FEM) for bodies of revolution is applied to the lens domain. The use of addition theorems for spherical modes allows the feeder to be arbitrarily translated and rotated. In this way, any modification in the lens or changes in the position of the feeder is quickly calculated, considering the mutual interactions between lens and feeder. The number of 2-D FEM simulations needed for lens analysis is discussed, as it will determine the efficiency of the method. Two very different examples are shown. One is based on a convex-to-concave spherical port connection, and the other on a convex-to-convex spherical port connection, for which a specific formulation is also presented.