Scattering of a Gaussian beam from the end-face of a waveguide system

The scattering of a Gaussian beam from the end-face of a waveguide system composed of a large number of cores is treated by the volume integral equation for the electric field and the first term of a perturbation solution for TE and TM wave incidence is analytically derived. The far scattered field does not almost depend on the polarization of an incident wave. Some numerical examples are shown.