Better multiband horn antenna design by using the real modal content at input

By taking into account the real modal content coming from the connected stage, instead of the fundamental waveguide mode only, a horn antenna can be designed to cope with the imperfections at its input. Unwanted higher order modes are often responsible for performance degradation and hence bandwidth limitation. The design procedure is applied for two types of horns, dedicated to different applications, but both with a wideband objective.