平台运动测量误差对阵列天线合成孔径雷达三维成像影响分析

Impact Analysis of Motion Measurement Error on Array Antenna SAR Three Dimensional Imaging

阵列天线合成孔径雷达(SAR)可实现3维成像。为了提高成像质量,使用测量设备获取平台的运动信息以进行运动补偿,而测量误差会影响补偿及成像质量,需对其进行分析。该文首先建立了阵列天线SAR 3维成像模型和测量误差分析模型,接着分别从位置和姿态角两个方面分析了测量误差对相位误差的影响,并比较不同方向误差影响的大小,然后通过仿真分析了误差对成像指标的影响,并引入姿态误差基线比来量化姿态角误差的影响。最后得出高程向和横滚角测量误差影响最大的结论,给出了限定要求下测量误差的容忍值。该文的结论为测量设备的选取和设计以及成像和补偿方法的选择和分析提供了理论指导和参考。

The array antenna SAR is able to realize the three dimensional imaging. In order to improve the imaging quality, the measurement equipment is adopted to acquire the motion information of the array antenna＇s platform for the motion compensation. However, the measurement error may impact the quality of compensation and imaging. Therefore analysis of the impact is indispensable. This paper establishes the imaging model and the measurement error analysis model, analyses the impact on phase error from the aspect of position and angle measurement error respectively, compares the impact of measurement error in the different directions, analyses the impact on imaging index by the simulation, and introduces the idea of angle-error-array-length-ratio to quantify the impact of angle error. The conclusion that the measurement error in the height and roll angle has the biggest impact is proposed and the error tolerance in certain conditions is given at last, which provides the theoretical guidance and reference for the choice and design of the measurement equipment and the motion compensation method.