Investigation on Two-dimensional Beam Steering of Spaceborne SAR Antenna

The requirements of spaceborne SAR system, especially SAR antenna is upgrated with the evolving performance of spaceborne SAR system. The beam steering capability of SAR antenna is developing to two-dimensional wide angle scanning. Therefore, calculation of two-dimensional steering angle of antenna is an important problem for the implementation of the system. In this paper, the definition of two-dimensional sterring angle and the geometry between the satellite and the earth of spaceborne spotlight SAR are introduced. Moreover, the formula of two-dimensional beam steering is derived. The verification of the formula is confirmed by simulation.