A CONJUGATE GRADIENT-BASED ALGORITHM TO MINIMIZE THE SIDELOBE LEVEL OF PLANAR ARRAYS WITH ELEMENT FAILURES

Element failures increase the sidelobe power level of an array. Reconfiguring the amplitude and phase distribution of the remaining elements can partially compensate for the failed elements and thus reduce the sidelobe level. The result of this investigation is an algorithm that yields the reconfigured distribution by minimizing the ratio of the average peak sidelobe power level to the power in the main beam, taking into account the defective elements. The minimization of this nonlinear function is carried out via a conjugate gradient method. The algorithm is applied to the synthesis of sum and difference patterns of planar arrays.