Design of frequency invariant response array based on steepest-descent algorithm

The design of the frequency invariant response array is formulated as an unconstrained optimization problem in this paper. The correlative objective function is presented based on the expression to describe the difference between actual and scheduled spatial response of the array. A new arithmetic is proposed to obtain the frequency invariant weight vectors by applying the steepest-descent algorithm. Computer simulations for uniform linear array and circular array have verified that the new method has high convergence precision and can be applied to arbitrary array without restriction on element patterns.