“…piecewise constant, discontinuous, Galerkin-type finite element approximation) have been developed on body-fitted coordinates [23], on unstructured finite element triangulations [4] or on totally destructured meshes [1]. First-order conservative upwind schemes, for which stability [19], convergence [8] and L 1 error estimates of h 1/2 [25] were proven, are too dissipative to be used for the Keywords and phrases. Electromagnetics, finite volume methods, discontinuous Galerkin methods, centered fluxes, leap-frog time scheme, L 2 stability, unstructured meshes, absorbing boundary condition, convergence, divergence preservation.…”