Comments on "Transmission from a Rectangular Waveguide into Half Space through a Rectangular Aperture" [Letters]

The authors of the above computer program description failed to acknowledge several publications dedicated to the same subject. An open-ended waveguide terminated by a flat infinite metal flange and radiating into an open half space of homogeneous, isotropic, and possibly Iossy medium was considered in [1]. The electromagnetic field distribution, the equivalent admittance of the aperture, and the reflection coefficient were presented. In another publication [2], the same approach was applied to radiation through a partial rectangular aperture; it was then also extended to radiation into a slab. The study of a rectangular cavity made from a section of open-ended rectangular waveguide was also treated and further developed in a third publication [3]. Computer programs have been available for all these problems on a complimentary basis and were widely distributed.