A hybrid Ewald-Spectral representation of the rectangular cavity Green´s function

A hybrid representation of the Green´s function of the rectangular cavity is presented in this work. When the observation point is near the source point, the Ewald representation of the cavity Green´s function is employed. When the observation and the source point are well separated, a two-dimensional (2D) spectral representation is used. Results show that the hybrid approach combines the advantages of the Ewald and the 2D-spectral representation while removing their drawbacks. As an application example, a reverberation chamber containing a mode-stirrer and a metallic enclosure is modeled.