波束中心近似对机载干涉SAR运动补偿的影响分析

为了定量分析波束中心近似对机载干涉SAR运动补偿的影响,该文首先建立斜视条件下波束中心近似时运动补偿残余误差的数学模型,其形式类似于斜距误差。随后推导斜视条件下二次斜距误差对干涉SAR的影响,通过仿真验证了理论推导的正确性。最后详细讨论不同波段、斜视角、轨迹偏移、地形变化和斜距情况下波束中心近似对干涉SAR运动补偿后图像质量和相干系数的影响。该文的分析结果为机载重轨干涉SAR数据处理中运动补偿精度的估计提供了技术支持。

Effects of Center-beam Approximation on Motion Compensation for Airborne Interferometric SAR

In order to analyze quantitatively the effects of Center-Beam Approximation (CBA) on MOtion COmpensation (MOCO) for airborne Interferometric SAR (InSAR), a mathematical model of MOCO residual error under the condition of squint is firstly established. The form of residual error is similar to the slant range error. Then, the effects of quadratic slant range error on InSAR are deduced on condition that the squint angle is not zero, and the accuracy of the theoretical derivation is verified with simulation data. Finally, the effects of CBA on image quality and coherence coefficient for airborne InSAR are discussed in detail for different bands, squint angles, trajectory deviations, topography variation and slant ranges. The research provides technical support for the estimation of MOCO precision in signal processing of airborne repeat-pass interferometric SAR.