Abstract:

For an airborne synthetic aperture radar (SAR) system with high resolution, the phase error caused by the changes of atmosphere refractive index in troposphere with height will affect the performance of imaging. The changes of atmosphere refractive index in troposphere with the Hopfield refractive model are analyzed, and the calculation of the apparent range between radar and ground targets is given. The mechanism of the influence of the changing atmospheric refractivity on the high resolution airborne SAR is also analyzed. The maximal imaging ranges of X band and Ku band SAR under different resolutions are given with a numerical method. In addition, the practical effect of atmospheric refractivity on the focusing of SAR imaging through simulation is presented.