Research On Aerial Target Detection And Imaging Method Based On Sparse Nodes And Time Reversal

This paper focuses on exploring the aerial target detection and imaging methods based on sparse nodes and time reversal.The basic theory and engineering application of sparse nodes time reversal are studied.Firstly,this paper introduces the focusing process of time reversal,and it presents the basic principle through mathematical derivation and physical explanation.On the basis of the channel transmission matrix,namely the multi-static response matrix,the time reversal operator is illustrated.Then the pseudo-spectrum of decomposition of the time reversal operator(DORT)and time reversal multiple signal classification(TR-MUSIC)are given respectively.Nextly,on the basis of the electromagnetic time reversal imaging framework,the equivalent research of algorithm is carried out for the application scenarios under multi-antenna excitation,and the full-wave simulation electromagnetic data is finally implemented in the calculation of the reflection of the antenna's port and the transmission response between the systems.Then,the imaging of different scenarios are given,including arraying on both sides of the targets and placing on the same side.The effects of the number of nodes,the distance between nodes,the distance from nodes to targets,the noise,and the number of targets on results are analyzed.The results show that the detection and imaging of long-range air targets can be realized under the condition of reasonable arrangement of transceiver nodes.Furthermore,based on the TR-MUSIC,the imaging of the extended target of multi-scattering center are realized.Finally,the feasibility of sparse nodes and time reversal imaging is proved by the experiment,which provides a new idea for practical engineering application.