<p>In the radio direction finding system, direction finding methods of Phase Interferometer have been widely applied, but because of its direction finding ambiguity, there is a contradiction between direction finding range and direction finding accuracy. In order to relieve the contradiction, multi-baseline phase interferometer is generally used to measure angles. However, this method is mainly aimed at one-dimensional angle measurement, so its system utilization is low. Therefore, a phase interferometer based on multiple antennas is proposed in this paper to measure the angle of pitch and azimuth in two dimensions, and the dual-baseline ambiguity resolution method is used to improve the accuracy of pitching angle measurement. Finally, the simulation results indicated that the theoretical analysis was correct</p>