SAR Echo Simulation Of Typical Terrain And Its Fast Implementation

Synthetic aperture radar(SAR)plays an important role resource exploration,military reconnaissance,aerospace and other fields for its unique all-weather,all-day and high-resolution characteristics nowadays.However,due to the limitation of time and the cost per flight,not all the SAR echo data can be completely collected by an actual airborne SAR radar in certain application.Therefore,the research of SAR echo simulation technology is of great significance.This thesis studies the three-dimensional model of real terrain,the calculation of scattering coefficient of real terrain and the algorithm of fast echo generation and its parallel acceleration scheme from the authenticity and efficiency of SAR echo simulation.The main contents of this thesis can be concluded as follows:(1)The thesis studies the random midpoint displacement interpolation method based on fractal principle,and the 3-D model of typical terrain is established with digital elevation model.The 3-D model is divided into small facets,the equation and the normal vector of the facets are solved,and the calculation method of backscattering coefficient based on small facets is studied to obtain scattering coefficients of different scenes.(2)According to the system geometry and signal transmitting and receiving process,the SAR echo model is established,the range history and the echo expression is derived.On this analysis,a high efficiency echo simulation algorithm of SAR based on sub-aperture and sub-scene is studied,which improves the low efficiency of traditional time-domain algorithm in the simulation of large scene.The effectiveness of echo simulation is verified.(3)In view of the low efficiency of SAR echo generation algorithm,the efficiency of algorithm execution and the specific flow of the algorithm is analyzed.The parallel scheme for the sub-aperture and the parallel scheme for both the sub-aperture and the sub-scene are proposed,the fast implementation of the algorithm is completed,and the transplantation of related code and the comparison of the relevant algorithms is finished.The results are simulated and verified with digital elevation model.Ideal results are obtained and the effectiveness of the above algorithm is verified...