电离层对中高轨SAR影响机理研究

Mechanism Study of Ionospheric Effects on Medium-Earth-Orbit SAR

中高轨道合成孔径雷达(Synthetic Aperture Radar,SAR)是下一代星载SAR重要发展方向之一,电离层影响分析是推动中高轨道SAR系统发展的关键技术之一。该文利用电离层实测数据分析了电离层时空变化特征,根据电离层时空变化特性,结合中高轨道SAR合成孔径时间长、测绘带宽、轨道高等特点,从SAR成像理论角度出发,分别从距离向和方位向阐述了电离层对中高轨SAR成像质量的影响因素和影响机理,通过分析揭示了中高轨SAR电离层影响与低轨SAR的不同之处。

The Medium-Earth-Orbit SAR（MEOSAR） is one of the potential spaceborne SAR of next-generation owing to its excellent performance. Ionospheric effects analysis is one of the critical techniques for the development of MEOSAR. The spatio-temporal variability of the ionosphere is analyzed using the measured ionosphere data. The factors and the mechanism of ionospheric effects on MEOSAR are studied based on the spatio-temporal variability of the ionosphere and the characteristics of MEOSAR such as long synthetic aperture time, wide swath, and high orbit. The results reveal that there are many differences in the ionospheric effects between MEOSAR and LEOSAR.