A surface integral method-of-moment formulation for dielectric loaded horns

Dielectric loaded horns have found widespread application due to their many attractive features. We present a surface integral method for the rigorous analysis of horns containing arbitrarily shaped dielectric structures and a waveguide aperture. The method is based on the PMCHWT formulation (named after Poggio, Miller, Chang, Harrington, Wu, and Tsai) (Chu, Y. et al., IEEE Trans. Antennas Propag., vol.AP-51, p.2837-44, 2003), which has hitherto been restricted to scattering problems. The numerical solution by the method-of-moments (MoM) allows the efficient calculation of the antenna pattern and of the generalized admittance matrix at the waveguide port, including higher-order modes for the intended further combination with fast hybrid MM/FE (mode-matching finite element) building blocks (Arndt, F. et al., IEEE Trans. Microwave Theory and Tech., vol.MTT-52, p.292-305, 2004.). The efficiency and accuracy of the method is verified by available measurements.