The major difficulty of realizing a micro-air-vehicle-borne (MAV-borne) synthetic aperture radar (SAR) is the motion errors that need to be precisely measured and compensated. This paper presents two novel motion measuring algorithms specifically for near-range applications. These algorithms use only low-cost micro-electronicmechanical system (MEMS) inertial measurement units (IMU). A MAV-borne SAR system was built equipped with a commercial off-the-shelf (COTS) motion sensing board. Several MAV-borne SAR measurements were performed for the first time in a hall with a realistic scene. SAR images were generated with proposed motion measuring algorithms in off-line mode. Obvious improvements in SAR image quality in terms of focusing have been observed after motion compensation with the proposed motion measuring algorithms. These results show that MAV-borne SAR together with low-cost IMU can yield very useful images.
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