Research On Moving Target Detection Technique Of Bistatic Ground Radar

Compared with traditional monostatic radar,the bistatic radar has stronger surviv-ability and anti-jamming performance.However,there is a problem of direct wave interference in target detection based on bistatic radar systems.In addition,with the emergence of mobile stealth aircraft,the detection of weak moving targets has also become a difficult point for bistatic radar systems.In view of the above problems,this thesis studies the direct wave interference suppression method and the long-term coherent accumulation target detection method based on bistatic ground radar.The main work is as follows:1.The bistatic ground radar system model is established.Then,the signal strength received by the target antenna and the reference antenna are analyzed in detail.Finally,the signal processing flow of bistatic ground radar target detection is given.2.For the direct wave interference problem in the bistatic ground radar system,the direct wave interference suppression algorithm is studied from the Doppler frequency domain,time domain and space domain.By analyzing the characteristics of direct wave suppression algorithms in different domains,the processing flow of direct wave suppression based on space-time joint processing is given.Finally,the suppression performance of each algorithm is analyzed through numerical simulation.3.For the long-term coherent integration target detection problem in the bistatic ground radar,the coherent integration algorithm based on GRFT(Generalized Radon-Fourier Transform)is studied.The search parameters and search step length of the GRFT algorithm are analyzed.For the blind velocity sidelobe problem of RFT algorithm,a blind velocity sidelobe suppression algorithm based on pulse repetition interval is studied.For the high computational complexity of traditional GRFT algorithm,a fast algorithm based on echo data segmentation is proposed.The computational complexity and multi-target detection performance of the proposed algorithm are analyzed.Computer simulation experiments verify the effectiveness of the proposed algorithm.Finally,a system simulation experiment is carried out according to the signal processing flow of bistatic ground radar target detection.4.A test platform based on bistatic ground radar is built,and the test steps and precautions are introduced.Data collection is carried out in the field.Through the analysis of the measured data,the feasibility of direct wave interference suppression through space-time joint processing is verified.