Analizing large reflectors antennas built with complex knitted meshes

New techniques for the analysis and design of large antennas systems which contain small-details geometries are presented. The specific purpose of this communication is the efficient analysis of parabolic reflector built with meshes of wires. The first technique considered is based on the combination of the Characteristic Basis Function Method (CBFM) and the Multilevel Fast Multipole Algorithm (MLFMA), which avoids the need of computing and storing all the terms of the reduced coupling matrix. The second technique is a domain decomposition approach. The geometry is compartmentalized into regions called windows, and we consider that only the current elements contained inside the same window are fully coupled. We compute then the interactions between different windows iteratively by applying ray-tracing. The third technique combines MLFMA-CBFM algorithm with the Impedance Boundary Condition.