New integral representation radiation boundary condition for the FDTD method

Considered is an integral representation of the electromagnetic fields anywhere in space in terms of known field values on a surface surrounding the calculation volume in order to derive a suitable radiation boundary condition (RBC). This particular RBC is referred to as the IRBC (integral representation radiation boundary condition). It is shown that the IRBC performs better than the classical RBCs but at the expense of increased CPU time requirements for the same calculation volume. However, the IRBC can be applied to sources close to the truncation boundary, leading to a smaller calculation volume, and in those cases where existing RBCs are known to be inaccurate.<>