Wide-band folding horn type microwave antennas

The authors illustrate the idea of a folding horn type antenna. The main difference from a traditional horn is its multipoint excitation. In ordinary horns the increase of aperture dimensions for a given length of the horn leads to undesirable quadratic phase variations of radiating field in its aperture. To avoid them a large length of the horn is essential. In a folding horn the necessary in-phase aperture field distribution is attained by its multipoint array type excitation.