Research On Target Direction Finding And Location Based On Aerostat

In the information age,direction finding and location technology is widely used in military,industrial,medical and daily life.Under the trend of modern integrated operations,direction finding and location is the core content of the electronic reconnaissance link.The detection range of the traditional active location system is limited by the transmission power,and faced with the threat of various interference and anti-radiation weapons.The passive location system has stronger concealment and wider detection range,which attracted the attention of the majority of research scholars.How to locate the radiation source target quickly and accurately is an important content in current research.This thesis mainly focused on the direction finding technology,single-station mode and multi-station mode location method in the direction-finding location system,and mainly completes the following aspects:1.In the multi-subarray structure,established a tensor model of the received data,and proposed a multiple signal classification algorithm based on tensor decomposition.Through the high-order singular value decomposition of the covariance tensor of the received data,obtain the tensor signal subspace and the tensor noise subspace.In the two expansion modes,using the orthogonality of the noise subspace and the steering tensor to search for spectral peaks and then estimate the direction of arrival of the target signal in the three-dimensional space.Simulation results show that the multiple signal classification algorithm based on tensor decomposition has sharper spectral peaks and better parameter estimation performance than traditional algorithms.2.According to the signal receiving model,proposed a signal parameter estimation method based on tensor CP decomposition.Using alternate least square method to obtain the factor matrixs in CP decomposition,then through Van der Mont property of the factor matrixs and the position of the array to calculate the azimuth and elevation of the target signal.Although this method has a certain loss in accuracy,it greatly reduces the calculation time and has high real-time performance.3.According to the azimuth and elevation of the target signal,which obtained by the direction finding part,use the cross location model to estimate the target position in the three-dimensional space by the motion single station mode.In the multi-station mode,using the direction finding information and the time difference of arrival information at the same time,proposed a AOA and TDOA fusion location method.Through simulation experiments,the performance of this fusion location method can be improved to a certain extent compared with the classical methods.