CAD-oriented, generalised admittance matrix approach for arbitrarily corrugated E-plane sectoral horns

The paper presents an efficient algorithm for the analysis and computer aided design of arbitrarily corrugated E-plane sectoral horn. This algorithm is based on the generalised admittance matrix method, which allows an efficient evaluation of the modal scattering matrix of cascaded discontinuities and junctions. The use of longitudinal section electric modes and of analytical or semianalytical expressions for calculating the modal reaction integrals for both the internal and the external regions, results in extreme speed-up of the overall procedure. Furthermore, an efficient connection scheme is implemented to save dynamic memory and inversion matrix CPU time. The results and the simplified assumption in the modal expression are successfully validated through comparisons with other numerical methods and experimental data. An example on dual-band corrugated horns is presented.