A hybrid finite element-boundary element method and its application to inverse scattering

A hybrid finite-element-boundary-element (FE-BE) formulation is applied to direct and inverse electromagnetic scattering from inhomogeneous scatterers. FEM is used in the inhomogeneous region, while BEM is applied to the external unbounded region. This hybrid method has the merits of both methods, i.e. the flexibility and sparse matrix of FEM for complicated inhomogeneous scatterers, and the easy handling with smaller nodes of BEM for unbounded regions. The numerical efficiency of this hybrid method makes it possible to apply this scheme to inverse scattering with least-square-error iteration. The accuracy of this formulation is checked by comparing the calculated results with an analytic solution for scattering from three-layer concentric infinite cylinders.<>