Comments on "Design of High Efficiency Circular Horn Feeds for Multibeam Reflector Applications

The above paper (K.K. Chan and S.K. Rao, 2008), has been read with considerable interest. We wish to point out that the design, including radiation and wide-bandwidth characteristics, of multiflared high-efficiency horns has already been published in an invention disclosure (A.K. Bhatacharyya and J. Sor, 2004) which has been in the public domain since June 8, 2006. The high-efficiency multiflared horn structure was first designed in 2003 at the company of the first author. Since then, the structure has been used as radiating elements for arrays and as reflector feeds in several communication satellite projects.