Efield MDMM — A new and innovative domain decomposition technique for advanced cavity problems

This paper describes Efield^® MDMM (Multi-Domain Multi-Method) a domain decomposition technique which may be used for a wide range of applications, including RCS of air intakes and exhausts, installation and interference of cavity antennas as well as analysis of antennas and waveguides. In Efield^® MDMM the geometry is divided into domains where different methods can be applied depending on what is most appropriate. For example consider a full aircraft model with integrated antennas, air-intakes or other detailed structures. When using Efield^® MDMM, antenna and cavity parts are typically solved by Method of Moments (MoM) or Finite Element Method (FEM) while Multi-Level Fast Multipole Method (MLFMM) or Physical Optics (PO) is used for the platform. This approach often leads to significant gains in terms of accuracy and efficiency. Applying MLFMM for the full problem often results in poor or no convergence due to the ill-conditioning of the resulting system. In this paper we present the Efield^® MDMM technique and show several examples which illustrate the efficiency of the method.