基于四维电子密度的地球同步轨道SAR电离层时变影响校正方法

Correction Method Based on 4-D Electronic Density of Ionospheric Effects Induced by Temporal Variability on GEOSAR

电离层在地球同步轨道SAR长合成孔径时间内具有明显的时变特性,这使得传统的基于电离层总电子含量(TEC)固定值的校正方法不再适用。为此,该文提出基于4维电子密度的地球同步轨道SAR成像补偿方法。通过基于电离层实测数据的半物理仿真,对校正方法进行实验验证,结果表明该方法可以有效地校正电离层时变特性对地球同步轨道SAR成像质量的影响。

The conventional correction method based on invariable TEC is no longer applicable to GEOSAR, because the temporal variability of ionosphere exits in synthetic aperture time of GEOSAR. In this paper, a correction method based on 4-D electronic density is put forward. This method is validated using actual data of ionosphere and the results indicate that this method can correct the ionospheric effects induced by temporal variability on GEOSAR effectively.