Abstract: The polarization characteristics of the log-periodic antenna are analyzed in this paper for the beamforming using circular array composed of horizontal log-periodic antenna. According to the theory of receiving antenna, a new manifold of circular array is deduced, and the inner polarization mechanism of array is expounded. Based on the new array popularity, the performance of the existing phase weighting beamforming method is analyzed theoretically and experimentally. It is pointed out that the phase polarization joint weighting should be adopted for the circular array beam synthesis of the horizontal log periodic antenna. The simulation results show that the joint weighting method can effectively improve the effect of the beamformer.