Determination of Dimensions and Shape of a Planar Aperture for Forming of Orthogonal Beams

A technique is proposed for determining dimensions and shape of a planar aperture which allows forming orthogonal beams arranged in the nodes of a general skew Cartesian periodic lattice specified in the plane of direction cosines. The technique is based on constructing an auxiliary lattice reciprocal with respect to the beam lattice, and on using one cell of the reciprocal lattice as the aperture required. The proof of orthogonality of the beams formed by the aperture chosen according to the technique proposed is given. Some examples are considered and characteristics of the orthogonal beams formed by an equilateral hexagon as an important special case are presented.