Simulation of reflector antenna covered by a circular radome

The effects of radomes have previously been studied by using such traditional approaches as local flat-slab approximation, local circularly curved surface approximation, thin-layer approximation, finite element solution, etc. For a canonical radome geometry like a circular cylindrical one, it is possible to derive the Green´s function in explicit form, by using the addition theorems for cylindrical functions. This enables one to write further an electric field integral equation over the reflector´s surface, and solve it by the moments method (MM). However, even for a free-space geometry, the MM results in prohibitively large CPU time, if a reflector is larger than 20 lambda. What is even more disappointing, the MM is known to be heavily inaccurate if a kind of shell resonance takes place. Therefore, in the present analysis the authors combine the Green´s function approach to account for the radome, with the method of regularization for solving the scattering from the reflector accurately. Besides, to simulate a directive feed in an equally accurate manner, the authors use the complex source point (CSP) concept. The latter is known as a very efficient way to account for the feed directivity without loosing mathematical correctness