Abstract:

The circular array interferometer with the analog phase detector requires a higher signal-to-noise ratio than the digital phase detector, which leads to the poorer performance, i.e. the lower ambiguity resolution probability and the lower direction finding (DF) accuracy. Two kinds of methods to improve the performance of DF are proposed. They are the modified phase accumulation method and the optimal baseline method. The modified phase accumulation method can improve the ambiguity resolution probability and DF accuracy, and the problem in conventional accumulation caused by the unique phenomenon of phase jump near ±π in the analog phase detector is solved. Taking the azimuth corresponding to one certain baseline pair as a reference, the azimuth and elevation corresponding to the baseline pair which has the highest accuracy are output, which improve the DF accuracy. Two kinds of methods can be combined. Simulation and measurement results show the effectiveness and correctness of these two methods.