On a simple method of obtaining sidelobe reduction over a wide angular range in one and two dimensions

A patented technique for suppressing the sidelobes of an array antenna is c onsidered. This technique involves the addition of two elements, one at eac h end of the array, which together produce an interferometer pattern used f or cancellation of side-lobes, It is shown here that the technique is most effective for uniform illumination and that there then exists an optimum fi xed position for the added elements, The amplitude of the excitation of the auxiliary elements determines the angular location of the region of sidelo be reduction while the phase of the excitation tracks the beamsteering phas e of the array. Thus, this technique is seen to be easily implemented in an array controlled by coupled oscillators, The technique generalizes in a st raightforward manner to two-dimensional (2-D) arrays in which case a set of auxiliary elements on the perimeter of the array is required. A 2-D oscill ator controlled array of this type is described here with which one can pro duce a main beam and a sidelobe suppression region that can be independentl y positioned anywhere in a hemisphere provided they do not coincide.