SAR Internal Calibration Technology Study

The SAR Internal Calibration (SIC) technique is indispensable for a spaceborne SAR system. In general, the SIC technique includes Internal Calibration (IC) theory, IC strategy and highly stable IC instrument. The IC task of phased array antenna SAR system is more complicated than that of TWT (Traveling Wave Tube) transmitter SAR system in many aspects, e.g. , T/R modules test, IC three loops construction and the process of IC data. However, there are lots of similarities between the two systems. In this paper, we only discuss the basic theory of the SIC based on the TWT transmitter SAR system and the process of the internal calibration data. Further, the precision analysis of the SIC will be given. Finally, we demonstrate the effectiveness of the proposed method based on the experimental SAR image.