Research On Single Station Passive Location Algorithm Based On Sparse Array

With the rapid development of information technology,electronic information technology has played a more important role in today's war situation.In the field of electronic countermeasures,the positioning of non-cooperative targets has been widely studied around the world.Different from active detection methods,such as radar and laser,which first transmitting signals to the radiation source and then detecting by receiving echoes.Passive detection is to locate the radiation source by detecting and estimating the electromagnetic wave parameters of the transmitter(radiation source)such as radar.Considering the inefficient and risky of the multi-station joint positioning method,this paper studies the single-station passive positioning whose application is more flexible.This paper mainly analyzes the source location model and related parameter estimation algorithms of passive sensing.In the aspect of passive locating model,this paper firstly introduces a classical single-station passive locating model with three observations.Since the classical model is very sensitive to the angle measurement error,a new locating model whose observations are only frequency differences is proposed in this paper.The proposed model needs to measure the frequency measurements of the two receiving devices at two moments to obtain observations.According to these observations,the observed targets can be located and tracked by appropriate filtering methods.In terms of parameter estimation,this paper introduces a relaxed coprime sparse array,which performs parallel undersampling on the incoming wave on each array element.This array structure can sequentially estimate the parameters(frequency and the direction of arrival)of the incoming wave with high precision within three array elements.Therefore,the parameter estimation results can be used as the observations of the locating system to perform the filtering operation.The simulation experiments show that,the proposed parameter estimation algorithm can accurately estimate the filtering observations,the frequency estimation error order is of 10^-10,and the estimation error order of the direction of arrival is 10^-3on the basis of the introduced array deploying with three array elements.After nonlinear extended Kalman filtering,the relative distance error of the proposed target tracking algorithm is in the order of 10^-4 when the filtering initial value is selected properly.This result is far lower than the classic single station passive locating method.Therefore,the proposed single-station passive locating algorithm based on relaxed coprime sparse array has a wide application prospect in the field of electronic countermeasures and passive sensing.