Asymmetry-symmetry decomposition: a new technique for efficient analysis of coupled antennas

The asymmetry-symmetry decomposition (ASD) technique is developed for the efficient method of moments (MOM) solution of coupled integral equations for surface currents on an asymmetrical structure, such as radiators with wire bends and microstrip discontinuities. The technique involves decoupling the symmetrical part of the problem and solving it by considering the resulting moment matrix symmetries. The method is illustrated by application to a microstrip bend discontinuity. Bent wire radiators in free space with structural and/or source-load asymmetries have been analyzed by ASD using MINNEC, and the predicted radiation field agrees well with measurements over a wide frequency range.<>