Rectangular waveguide Green´s function involving complex images

Waveguide Green´s function is a powerful tool for analyzing discontinuity problems in a waveguide. The rectangular waveguide Green´s function has been extensively investigated previously. Recently the Green´s function for a partially filled rectangular waveguide has been presented. In the derivation of the Green´s function, to match the boundary conditions both on the conducting walls and the dielectric interfaces, the real images are used. In this paper, all the images are replaced by the full wave discrete images which are complex. Compared to the existing rectangular waveguide Green´s function, the Green´s function proposed in this paper possesses some advantages of being efficient and fast convergent. The numerical results confirm the validity of this Green´s function.