Recalculating linear array antennas to compensate for failed elements while maintaining fixed nulls

Given the failure of one or more elements of an array antenna designed to produce a radiation pattern including nulls in arbitrarily fixed directions, a pattern with the desired side lobe level and nulls can often be recovered by modifying the excitations of the non-defective elements. The modified excitations can be calculated by simulated annealing using an appropriate cost function.