Optical Imaging System Of SAR Based On Deformable Mirror Phase Compensation

Synthetic aperture radar(SAR)is widely used in civil and military fields.There are many efficient digital imaging algorithms in SAR imaging field.In recent years,SAR optical imaging technology has also made new progress.In practical application,because of the uncertainty of the aircraft platform motion,the phase error in the echo signal will lead to the degradation of imaging quality.In this paper,a optical imaging system of SAR based on deformable mirror phase compensation is proposed.Based on the mathematical model of SAR echo signal,this paper reviews the common digital imaging algorithms: Range Doppler algorithm,Chirp Scaling algorithm and wavenumber domain algorithm.These algorithms provide a reference for optical imaging processing.The related principles of optical imaging system such as Fourier optics and Zernike polynomials are introduced.The application of lens,spatial light modulator and deformable mirror in SAR optical imaging system is studied.The structure of SAR optical imaging system based on deformable mirror phase compensation is given,and the feedback mechanism of imaging system is studied.Deformable mirror is the key device in imaging processing.Its main function is to fit the curved surface according to the system parameters to compensate the echo signal in frequency domain,and adjust the surface shape according to the imaging results,reduce the phase error and improve the imaging quality.In this paper,the imaging system is simulated according to relevant theories,including the simulation of deformable mirror's shape variable,imaging simulation based on phase compensation of deformable mirror and imaging feedback simulation.The feedback mechanism can effectively improve the imaging quality of the system and enhance the adaptive ability of the system.