Comments on “on the Power Absorbed and Scattered by an Antenna” [Letter to the Editor]

In a very interesting recent paper, Dr. Steyskal studied the power absorbed and scattered by an antenna. His comment on the total field in the forward direction could be considered from a slightly more general point of view. According to, the for ward scattering could be considered as a shadow radiation, which does not depend on the whole shape of the scattering object, and is completely determined by the size and the geometry of the shadow contour. Its power equals the total power incident on a scattering object, and it does not depend on the reflection coefficients. This quantity can be considered to be the diffraction limit of the reduc tion of scattering by application of absorbing coatings on a scat tering object. That actually means that the shadow radiation con tains a component in the form of the edge waves diverging from the shadow contour.