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复杂的机载合成孔径雷达系统使得探测精度要求研究难以系统有效.依据辐射定标精度在机载合成孔径雷达海面风场探测信息流程中的作用,提出通过辐射定标精度要求整体考察系统探测精度要求的研究方法,仿真研究了CMOD4地球物理模型函数的参数关系,系统地确定出不同入射角和风向条件下机裁合成孔径雷达海面风场探测的辐射定标精度要求.研究结果表明,辐射定标精度要求随着入射角的增加而降低,且随着风向变化呈周期性变化,这一规律与CMOD4地球物理模型函数中由风速变化引起的后向散射截面变化值的变化规律一致.依据这一规律,研究发现通过采用有源定标器定标、设计载机做侧风飞行以及选择大入射角的探测图像作为反演图像区这三种手段,能够提高风速反演精度.
The complicated airborne synthetic aperture radar (SAR) system makes it difficult to systematically study the requirements of the detection accuracy.According to the role of the radiation calibration accuracy in the information flow of the sea surface wind field detection of airborne synthetic aperture radar, it is proposed that the overall accuracy of the system detection accuracy The required research methods are used to simulate the parameters of the CMOD4 geophysical model function and to systematically determine the radiation calibration requirements for the wind field detection of machine-tailored synthetic aperture radar under different incident angles and wind directions.The results show that the radiation The accuracy of the standard decreases with increasing incident angle and changes periodically with the change of wind direction, which is consistent with the change law of the backscattering cross-section variation caused by wind speed in the CMOD4 geophysical model function.Based on this As a rule, the study found that the accuracy of wind speed inversion can be improved by using three methods: calibration by active scaler, designing cross-wind flight on aircraft and selecting the detection image with large incident angle as the inversion image area.