Efficient finite-element solution for the problem of scattering from multiple cavities and holes

Efficient finite-element solution for the problem of scattering from multiple cavities and holes in infinite metallic walls is described. The surface integral equation using Greenpsilas function of the first kind is derived and applied as a boundary condition to truncate the mesh region. The solution efficiency of the method presented here is significantly greater than solutions that would be obtained using commercial finite element solvers.