The airborne X-SAR calibration with high resolution

X-SAR system is the airborne imaging radar with multi-mode synthetic aperture radar (SAR) at high-resolution, interferometer and full-polarization, which has been developed by the Institute of Remote Sensing and Digital Earth (RADI), Chinese Academy of Sciences (CAS), funded by the CAS Large Research Infrastructures. From 2009 to 2015, the first-stage project has been accomplished. X-SAR system was successfully implemented to an operational SAR in X-band with high spatial resolution (up to 0.5 meter). A flexible internal calibrator has been integrated in X-SAR radar, which can be guaranteed the outstanding performance of image products, regardless of operated on in-flight data acquisition and on laboratory measurements. All calibration results of X-SAR system were emphasized the quantitative measurement capabilities. The radiometric enhanced products of intensity change detection has been supplemented, in which X-SAR calibrated images products at 0.5 meter spatial resolution have be already achieved the image located precision less than 2.7 meter and long-term radiometric stability better than 0.5dB. This paper summarizes the behavior of the internal calibrator, meantime describes the essential results of the internal and external calibration.