Non-reflective planar boundary condition based on Gauss filter

A non-re ecting boundary condition based on the Gauss lter is employed for the determination of scattered potential governed by the Helmholtz equation. A ltering layer is used for closing in nite domain calculations. An expression for the re ection coe cient is derived and an optimal ltering layer is designed. Numerical results validate the performance of this method for unbounded wave guide problems