基线抖动对干涉SAR相位的影响

Influence of baseline oscillations on SAR interferometric phase

提出并分析了基线抖动造成的干涉SAR相位误差模型。基于干涉SAR基线抖动模型,分为水平抖动和垂直抖动,推导了存在基线抖动情况下辅天线复图像信号模型及基线抖动带来的干涉相位误差公式,分析了基线抖动对成像质量和干涉相位的影响,针对SRTM系统进行了计算机仿真。通过基于基线抖动的干涉SAR原始回波数据计算,仿真了点目标和面目标场景的回波信号,并进行成像得到了复图像和干涉条纹,仿真结果验证了理论分析的正确性。

A model analyzing the effect of baseline oscillations on InSAR phase error is presented in this paper. By a baseline oscillations model, which includes horizontal oscillation and perpendicular oscillation, the models for SAR complex image of slave antenna and interferometric phase error are both deduced. Then effect of baseline oscillations on interferometric phase and quality of SAR image is analyzed. At last, a computer simulation on SRTM system is given. Through raw signal simulation of InSAR in time domain, raw signal for point target and extended scene targets are simulated. After imaging, complex image pairs and interferometric phase are obtained. The simulation results proved the validity of analysis.