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This article concerns the analysis and compensation of track deviations in high-resolution automobile synthetic aperture radar (SAR). We establish the geometry in which the automobile-SAR raw data is acquired. Based on the derived model, the research investigates the impact of track deviations on the final focused image quality and we propose a motion compensation strategy which can be applied to obtain a well-focused SAR image. This article presents how to obtain the accurate positions of the antenna phase centre using the velocity and attitude angles measured by inertial navigation system/global positioning system, and proposes a new method to compensate for forward velocity errors which are decomposed into two components and compensated individually, that is, high-order and low-order phase compensation. Finally, the results from both simulated data and real data are presented to validate the whole analysis and the proposed procedure. [ABSTRACT FROM PUBLISHER]

In this paper we investigate the possibility to produce high‐resolution synthetic aperture radar (SAR) images of wide areas from the data collected by the distributed small spaceborne SAR systems. In particular, we focus on the data processing techniques for overcoming the Doppler ambiguity effects characterizing ground echoes and achieving high‐resolution SAR images of wide areas. A novel approach is proposed, the key idea of which is to retrieve the unambiguous azimuth wide (full) spectrum signal from the received ground echoes by using a space–time adaptive processing (STAP) algorithm to overcome the Doppler aliasing effect induced by the lower pulse repetition frequency (PRF); following this operation, conventional SAR data processing tools can be applied to fully focus the SAR images. The STAP‐based approach has the advantages of simplicity, robustness and high efficiency. We also discuss the array configuration requirements, and give a platform velocity/PRF criterion for array configurations. [ABSTRACT FROM AUTHOR]