Characteristic-absorption: a general method to improve absorbing boundary conditions [EM scattering]

The characteristic-absorption scheme is shown to be successful in reducing the reflection of the first order Mur scheme (1981). It produces a reflection approximately similar to that of the second order scheme in three dimensions. Also, in three dimensions, the corrected first order scheme suffers less from the spurious modes of the second order Mur scheme. The characteristic-absorption technique applied to the first order Mur scheme does not require a special corner treatment, it can be applied in the corners without alteration. Note that this new form of correcting the absorbing boundary condition is not specific to the Yee algorithm and can be applied to other hyperbolic problems