Efficient Electromagnetic Scattering Analysis of Open-ended Circular Cavities with Modal MoM Method

摘要

An efficient and accurate technique is introduced to calculate the scattered electromagnetic (EM) fields from an open-ended circular cavity (OECC). In this paper, it is assumed that the OECC is perforated in an infinite perfect electric conductor (IPEC). Then, the scattered fields are calculated using modal Method of Moments. The complexity and computational cost of the encountered quadruple integrals are addressed in detail. Here, the singularities are extracted and resolved. Next, the scattered far field of a circular PEC plate of the same size is calculated by physical optics approximation. The final OECC scattered field is the sum of these two solutions. A very good agreement is observed between the results of this method and full wave numerical simulations and measurements. The proposed approach is highly efficient and accurate over a wide range of frequencies and incidence angles, making it appealing for analysis of large frequency dispersive structures.