In phased array systems, beam pointing accuracy is one of the major issues for its great effect on radar communication. Regardless of the initial excitation error and the inherent mutual coupling between antenna elements, the anisotropy of antenna element's radiation pattern is the main reason for beam pointing error. In this paper, we propose a closed-form solution of compensating for beam pointing error with uniform linear arrays. It gives a theoretical explanation how beam pointing deviates from the desired angle when scanning angle and the number of elements vary. Then a numerical simulation validates the effectiveness of the proposed theory. Finally, an experiment with an X-band phased array verifies that the closed-form solution can be applied to practical phased array systems in the presence of mutual coupling.
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