ABSTRACT
Abstract . In this paper we consider the problem of the scattering of a plane wave by a three dimensional perfectly conducting bounded object . We embed the object in a sphere on the boundary of which we apply an absorbing boundary condition. The harmonic Maxwell equations are discretized with conforming PI finite elements in [HI (nw on tetrahedrons . The perfectly conducting boundary condition on the object is handled via Lagrange multipliers . This amounts to solving a sparse symmetric in definite linear system with complex coefficients. Iterative methods like GMRES and Bi-CGSTAB are described for solving this problem with suitable efficient precondi tioners . Numerical experiments for several model problems are given.
