Phase-only nulling as a least-square approximation to complex weight nulling

A solution is presented to the problem of obtaining a least-squares fit of phase-only array weight perturbations to a set of combined phase and amplitude perturbations calculated to impose pattern nulls at prescribed sidelobe directions. It is shown that the desired least-squares fit is accomplished by taking only the phase part of the combined phase and amplitude perturbations. This method of phase-only nulling is compared in effectiveness with other phase-only pattern synthesis methods.