This paper investigates a new method for synthesis of the hexagonal antenna array. The local convergence of the nonlinear least-square method is restricted by selecting several initial values, such can achieve the global optimization of the antenna array. According to the elements symmetry distributed in axis, the scattering coeffecient of whole antenna array can be achieved by calculating part of elements, and abase the influence by mutual coupling . Simulation results show the pattern of antenna array approaches the objective pattern in the least square sense.
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