Optimized planar array antenna nulling with phase only control

A new theoretical method is derived by which a planar array antenna can provide maximum antenna gain in a specified pointing or look direction while simultaneously imposing J nulls in J directions. This is all accomplished by only varying the phase setting at each element of the array. Thus any amplitude taper can be applied to the array. In the transmit mode unity amplitude weighting is desired so that all elements transmit the same power, In the receive mode a taper is desired for the generation of lower sidelobes. The required nulls in the transmit and receive antenna patterns can be provided with this method. Typical examples are presented for this method and the degradation with system errors (i.e. phase errors in each channel) is evaluated. Antenna pattern plots are presented for a planar array composed of several thousand elements spaced on a triangular grid.