A method to estimate the effects of the antenna jitters of an agile SAR satellite on the appearance of the images

作者：Pang Yan^*; Huang Mo; Zhang Rui; Liang Xuwen

来源：Journal of Computational Information Systems, 2014, 10(10): 4319-4329.

DOI：10.12733/jcis10320

• Agile satellites
• Antenna directions
• Estimation performance
• Geometric fidelity
• High-resolution SAR
• Phase corrections
• Processing algorithms
• Series-based methodology

Efficient synthetic aperture radar (SAR) processing algorithms are unable to compensate envelope errors caused by the instability of the antennas; because the traditional motion compensations (MoCo) of SAR processing performs only phase corrections. During the motion compensation, the antenna direction is assumed stable, resulting in azimuth envelop errors which impact the resolution and the geometric fidelity of the processed SAR images. This paper proposes a Fourier transform-and Taylor series-based methodology capable of precisely estimating the effects of the pointing jitter on the appearance of the radar image. In addition to the overall system design of the agile SAR satellites, the theoretic research of the motion compensation can also benefit from this approach, especially for the a high-resolution SAR system with a narrow beam placed on an unstable platform. Data from a simulated X-band SAR system with pointing jitters are used to demonstrate the estimation performance of the proposed approach.