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Commission I, WG I/1 KEY WORDS: Airborne InSAR, residual error, time-varying baseline, ground deformation ABSTRACT:Short temporal baseline and multiple ground deformation information can be derived from the airborne differential synthetic aperture radar Interforemetry (D-InSAR). However, affected by the turbulence of the air, the aircraft would deviate from the designed flight path with high frequent vibrations and changes both in the flight trajectory and attitude. Restricted by the accuracy of the position and orientation system (POS), these high frequent deviations can not be accurately reported, which would pose great challenges in motion compensation and interferometric process. Thus, these challenges constrain its wider applications. The objective of this paper is to investigate the accurate estimation and compensation of the residual motion errors in the airborne SAR imagery and time-varying baseline errors between the diffirent data acquirations, furthermore, to explore the integration data processing theory for the airborne D-InSAR system, and thus help to accomplish the correct derivation of the ground deformation by using the airborne D-InSAR measurements.* Corresponding author: Prof. Huadong Guo. Email: hdguo@radi.ac.cn; doucy@radi.ac.cn INTODUCTIONAs a major source of remote sensing data and with its unique merits of penetrating clouds and rain, and independence of sun illumination, synthetic aperture radar (SAR) has become increasingly important in Earth observation applications. Among them, Ground deformation detection is one of the important applications for the SAR interferometry (InSAR) (Massonnet and Feigl 1998). Compared with spaceborne sensors, airborne InSAR, owing to the peculiarities of its platform, features higher spatial resolution and greater flexibility in the investigation, thus, allowing it to obtain wide temporal baseline (hours to years) and multiple directions ground deformation information (Prats et al. 2008). Nevertheless, affected by the turbulences of the air, the aircraft would deviate from the designed flight path with high frequent vibrations, as well as changes in the flight trajectory, attitude and forward velocity variations. Restricted by the accuracy of the position and orientation system (POS), these high frequent diviations can not be accurately reported, which would pose great challenges in following motion compensation and interferometric process. Uncompensated motion errors would cause artefacts in the images, among which the most important are geometric distortions and phase errors. Although, such small errors are can be neglected in most applications, this is not the case for repeatpass differential SAR interferometry (D-InSAR) applications (Zhong et al. 2012;Zhong et al. 2014). Unlike with the singlepass airborne InSAR systems, residual motion errors of each flight track are independent and do not cancel out during interferogram generation, the residual motion errors would pose great challenges to derive accurate phase information from the co-registered image...