Research On Influence Of Array Failure On Interferometer Direction Finding Algorithm

Interferometer direction-finding system is one of the passive direction-finding,due to the high accuracy of direction finding and simple algorithm,it’s widely used in electromagnetic environment monitoring and electronic countermeasure.The interferometer depends on the phase information generated between array elements by waves to calculate the azimuth.The influence on the performance of interferometer mainly depends on the array mode and direction finding algorithm.When the array element of interferometer fails,the direction finding performance of interferometer will be seriously affected.However,interferometers usually work outdoors.Due to the influence of bad natural environment,human interference,aging of array elements,physical damage of array elements and other factors,the failure of array elements is inevitable.For the failed array element,the most direct method is to repair the fault element of the channel,but in most cases,repairing the fault element is not the most economical and effective method,and it is not easy to implement.For example,in the war,the timeliness of direction finding is very high,and the replacement of satellite equipment is difficult due to the long distance.It is of great engineering value to study the influence of array element failure on direction finding algorithm of interferometer.This article mainly focuses on the defuzzification ability of several interferometer direction finding algorithms in the case of element failure.In-depth analysis of the defuzzification probability of linear arrays and circular arrays in different array element positions and numbers of failures.Combining with the study of element failure,an interferometer array method and direction finding method suitable for a platform with limited array space are proposed.Details as follows:(1)This article introduces the basic principle of interferometer direction finding and several commonly used defuzzification algorithms,and describes in detail the interferometer antenna structure,baseline constraints and defuzzification principles in each algorithm.(2)In this paper,by constructing a one-dimensional linear array interferometer direction-finding model,the defuzzification probability of the two algorithms is analyzed in the case of each element failure.And the paper explored the distribution characteristics of array elements that have a greater impact on the probability of defuzzification;(3)In this paper,Three direction finding algorithms for two-dimensional uniform circular array are studied,namely,the parametric baseline method,the three-dimensional baseline method,and the parallel baseline method.The effects of the number of failures and the position of the array element on the three algorithms are analyzed separately.The defuzzification probability statistics chart of the algorithm is given in the case of array element failure.(4)Combined with the research conclusions on one-dimensional linear arrays and uniform circular arrays,a non-uniform L-array is designed for some equipment on platforms with limited array space,and the virtual baseline method can be used to solve the phase ambiguity.This layout method can still be effective in the case of a single element failure,and the negative impact would lose a certain degree of ambiguity solving probability and angle measurement accuracy.Through simulation experiments,the defuzzification probability of the algorithm under different signal noise ratios and phase errors is analyzed.,and the loss of angle measurement accuracy and ambiguity solving ability in the case of element failure are analyzed,and they are all within an acceptable range,verifying the feasibility of the algorithm.