Bistatic SAR Forward-looking Imaging And Signal Processor Design And Implementation

By setting the receiver and transmitter on different platforms,Bistatic synthetic aperture radar can realize high resolution imaging of the area directly in front of radar,which has the characteristics of good anti-interference,strong concealment and good antiinterception.Bistatic synthetic aperture has gradually become a research hotspot in the field of radar.It is a research hotspot in the radar field and has important application value in the fields of precision guidance and autonomous landing.This thesis focuses on the Bistatic forward-looking SAR imaging and signal processor design,and carries out research on polar format algorithm,signal processor hardware design and imaging algorithm FPGA implementation.The main contents are as follows:(1)Aiming at the specific spatial geometry of bistatic forward-looking SAR,the echo model is established,The echo law is analyzed from the aspects of distance history and Doppler characteristics,and the influence factors of resolution are analyzed for subsequent imaging.Algorithm research provides theoretical guidance.(2)Aiming at the problem that the classical polar format algorithm will cause poor azimuth focusing effect when it is applied to bistatic forward-looking SAR with large slant Angle,a polar format algorithm based on function mapping is designed.The simulation proves that this method can obtain good focusing effect on the bistatic forward-looking SAR platform.(3)Aiming at bistatic forward-looking SAR imaging algorithm flow and the function requirements of the signal processor.a high-speed signal processor scheme based on VPX architecture was designed,and the device selection and hardware circuit design of the data acquisition board and signal processing board were completed.(4)According to the hardware resources of the signal processor and the characteristics of the imaging algorithm,making full use of the high parallelism of FPGA,using pipeline and ping-pong operation design idea,the program design of imaging algorithm based on FPGA is completed,as well as the debugging and imaging verification test of signal processor system.The above research work has been verified by functional simulation and test experiments.