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http://dx.doi.org/10.5139/JKSAS.2020.48.4.285

Analysis and Compensation of Time Synchronization Error on SAR Image  

Lee, Soojeong (Department of Mechanical and Aerospace Engineering/ASRI, Seoul National University)
Park, Woo Jung (Department of Mechanical and Aerospace Engineering/ASRI, Seoul National University)
Park, Chan Gook (Department of Mechanical and Aerospace Engineering/ASRI, Seoul National University)
Song, Jong-Hwa (Avionics Radar Team, Hanwha Systems)
Bae, Chang-Sik (Avionics Radar Team, Hanwha Systems)
Publication Information
Journal of the Korean Society for Aeronautical & Space Sciences / v.48, no.4, 2020 , pp. 285-293 More about this Journal
Abstract
In this paper, to improve Synthetic Aperture Radar (SAR) image quality, the effect of time synchronization error in the EGI/IMU (Embedded GPS/INS, Inertial Measurement Unit) integrated system is analyzed and state augmentation is applied to compensate it. EGI/IMU integrated system is widely used as a SAR motion measurement algorithm, which consists of EGI mounted to obtain the trajectory and IMU mounted on the SAR antenna. In an EGI/IMU integrated system, a time synchronization error occurs when the clocks of the sensors are not synchronized. Analysis of the effect of time synchronization error on navigation solutions and SAR images confirmed that the time synchronization error deteriorates SAR image quality. The state augmentation is applied to compensate for this and as a result, the SAR image quality does not decrease. In addition, by analyzing the performance and the observability of the time synchronization error according to the maneuver, it was confirmed that the time-variant maneuver such as rotational motion is necessary to estimate the time synchronization error adequately. In order to reduce the influence of the time synchronization error on the SAR image, the time synchronization error must be compensated by performing maneuver changing over time such as a rotation before SAR operation.
Keywords
Synthetic Aperture Radar; EGI/IMU Integrated System; Time Synchronization Error;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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