Height resolution analysis in geosynchronous SAR

Owing to the curved track, geosynchronous synthetic aperture radar (GEO SAR) can obtain a height resolution. An accurate expression of the height resolution is derived for GEO SAR based on the generalised ambiguity function and the Doppler history difference between two adjacent targets at different heights. It is found that the height resolution is introduced by the accelerated motion or the curved track along the height direction in GEO SAR. Then, factors influencing the height resolution are analysed. The height resolution of GEO SAR can be improved by a longer integration time, a higher orbital inclination and a larger eccentricity. Finally, simulation results show the effectiveness of the proposed expression of height resolution.