Research On Single Station Passive Location Algorithm Under Short-duration Observation

Single station passive localization has important value in fields of electronic warfare due to its safety and mobility during positioning.The existing positioning methods can be roughly divided into direct position determination method and two-step position determination method.Among them,the two-step position determination method firstly estimates the location parameters,and then uses the intermediate parameters to achieve positioning.Since the two-step method usually does not require additional prior information and has an analytical solution without scanning algorithms,it has certain advantages compared to the direct positioning method.However,because the positioning information is given by the positioning parameters,the estimation accuracy of these parameters will directly influence the positioning accuracy.Therefore,high-precision estimation of the positioning parameters becomes the focus of the two-step positioning method.This paper starts with the positioning model,simplifies the expression of the positioning model,and analyzes the required positioning parameters,which divided into frequencyrelated parameters and angle-related parameters.For frequency-related parameters,a dual estimation method combining coarse scanning and fine scanning is adopted: the coprime spectrum analysis method based on IDFT filtering banks can effectively realize high frequency estimation in the under-sampling after improvement of filter grouping.Considering the factors such as hardware cost and estimation accuracy,the prime spectrum analysis algorithm is used as a rough scan of the received signal to determine the approximate range of the signal frequency.The frequency estimation algorithm based on the closed-form robust Chinese remainder theorem has low hardware complexity and high estimation accuracy,which is used for high-precision frequency estimation of the received signal in the target frequency range.Then,based on the high-precision frequency estimation,combining the estimation of rate-of-change parameters with the observation time,this paper proposes an estimation algorithm of Doppler rate under short-duration observation,and derives the short-duration observation condition as the precondition of this algorithm.For anglerelated parameters,this paper studies the array structure and DOA estimation algorithm,obtains the arrival angle estimation by the coprime sparse array,and realizes the estimation of the angle rate.In this process,the short-term observation conditions are also applicable.Finally,in order to test the performance of the positioning algorithm,a set of signallevel simulation experiments are designed.The simulation process is not the simulation estimation of a single parameter,but the operation of array reception signal,high frequency analog signal under-sampling,parameter estimation,positioning realization,etc.,which completely simulates the whole process of locating the target sources.The simulation results show that the positioning algorithm designed in this paper has the advantages of high positioning accuracy,short observation time,and wide applicable frequency bands.