Based Phase Interferometer Positioning Technology, To The Algorithm

The arrangement of arrays and the algorithm in the finding direction by the method of interferometry system and the performance of system are studied in this dissertation. The interests focus on resolving the ambiguities of Angle of Arrival and increasing the accuracy of finding direction system.Firstly, the basal principle and the mathematical model of the finding direction by the method of interferometry are introduced. The factors taking effect on the accuracy of the interferometer used for finding direction are investigated generally, and an effective way to advance accuracy that increasing the length of baselines and decreasing the angle between the incident wave and the normal of the baseline is introduced.Secondly, the traditional finding direction by method of interferometry system and the long baseline finding direction by method of interferometry system and the algorithms applied by them are researched. The traditional finding direction by method of interferometry system makes use of the combination of long baseline and short baseline. It ably applies the feature deducing the only angle from the short baseline and the accuracy of the angle calculating from the long baseline, and uses the data measured by short baselines to dispel the ambiguities of Angle of Arrival concluded by the long baselines. The algorithm led by small aperture base can calculate the angle of arrival from 0 degree to 360 degree. Long baseline finding direction system utilizes the algorithm for finding direction with baselines having enough length, and the length of baseline can be long enough. With the algorithm provided, the ambiguous zone which can be resolves in the interferometer and the maximum of the length of the baselines can be obtained.The least square direction-finding method is given by applying the least square method to the measured phase value. With the method, all the information included in the phase can be used to determine the Angle of Arrival. Because the larger error of Angle of Arrival can not occurs for the incident wave in all the direction in half space, this method has a stable high accuracy.Lastly, the finding direction systems by method of interferometry are simulated. The recover of the incident wave signal is studied from the point of view of the practical significance. The results of the direction-finding simulation are given that measured from the arrays with a shape of the "L", four baselines system and five baselines system etc. The data provide the many bases to make sure the scheme of finding direction system with interferometer.