Reflectionless sponge layers for the numerical solution of Maxwellʹs equations in cylindrical and spherical coordinates Original Research Article

We review the scaling argument used to derive reflectionless wave absorbing layers for use as Absorbing Boundary Conditions (ABC) in numerical solutions of the elliptic and hyperbolic Maxwell equations in cylindrical and spherical coordinates, and show that thus obtained absorbing layers are described in the time-domain by causal, strongly well-posed hyperbolic systems. Representative results are given for scattering by cylinders. Also, we study the reflection of local ABCʹs in discrete space.