An Algorithm for Motion Compensation in Synthetic Aperture Radar (SAR) Based on Real-time Sub-aperture (RTS) Image Formation Algorithm

Document Type : Original Article

Author

Assistant Professor, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology

Abstract

In this paper an algorithm based on the real-time sub-aperture (RTS) algorithm is presented for phase error estimation and compensation of synthetic aperture radar (SAR) in the case of
non-ideal platform motion. In the proposed algorithm, the signal is input into the RTS algorithm, then extracting the peak time of different sub-aperture processing channels, the phase gradient of peak times is computed and after integration and interpolation, the estimated phase error is compensated in the received signal and finally the RTS algorithm is executed again in order to form the final image. Using the proposed algorithm, the motion compensation (autofocus) ability can be added to the RTS algorithm without changing its processing core whilst keeping the real-time capability. Simulations show the effectiveness of the proposed algorithm for compensating phase errors due to motion fluctuations of the radar platform.

Keywords


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Volume 7, Issue 1 - Serial Number 21
December 2019
Pages 25-38
  • Receive Date: 22 April 2019
  • Revise Date: 19 August 2019
  • Accept Date: 15 September 2019
  • Publish Date: 18 September 2019