Research And Implementation Of Large-squint SAR Imaging Algorithm Based On Missile-borne Platform

With the rapid development of the synthetic aperture radar industry,strike accuracy can be improved by applying SAR to a missile-borne seeker which matches target landscape images by high-resolution imaging,which has important military significance.As one of the most important methods of modern communication technology,the theory and imaging technology are crucial to the performance of the whole system.The missile-borne seeker usually requires high-precision imaging with the front-side view while the missile is affected by the air flow,so the flight trajectory changes greatly and randomly during air flight.And in the meanwhile,the missile-borne SAR requires real-time performance.For the reason above,higher accuracy and efficiency is necessary for the algorithm.This article has done a lot of in-depth research on the imaging algorithm and missile motion compensation based on inertial navigation data of missile-borne SAR imaging,then designed a signal processor.As the result of simulating and comparing the imaging results of different oblique-angle targets with CS and ?K algorithms,the ?K imaging algorithm is more suitable for highsquint SAR system in terms of computing efficiency or imaging accuracy.By researching and analyzing the movement model of the missile during actual flight,compensation algorithms for the correction of the phase changes caused by the movement errors are carried out in the sight direction and the flight direction respectively.The improvement of compensation algorithm for different oblique angle is studied.This paper gives the ?K imaging algorithm combined with the real-time motion compensation method and the motion compensation simulation under different oblique angles,which proves the effectiveness and simplicity of the algorithm.Finally,a missile-borne SAR imaging signal processor based on TMS320C6678-DSP is designed.This design uses the hardware structure of FPGA and DSP,which can better undertake the design of complex timing and signal processing algorithm tasks.This paper introduces the software architecture and system specifications of the signal processor.Then the programme for the algorithm above on the DSP is designed,which has been verified by software simulation.