Beam-mode analysis of a slotted horn antenna suitable for micromachined rectangular waveguide

This paper describes a Gauss-Hermite beam-mode analysis of the far-field radiation pattern of a sectoral horn antenna with a tapered slot in its upper broadwall. This type of antenna is suitable for integration with micro-machined rectangular waveguide. Examples having been fabricated for frequencies as high as 1.6 THz. Microwave scale model radiation pattern measurement are presented. A procedure for carrying out a beam-mode analysis from the measured far- field pattern rather than the usual case of a theoretical near-field distribution is described. The beam-mode analysis technique is of general applicability to all types of antenna.