Improved precise tomography- and aperture-dependent compensation for Synthetic Aperture Radar

Abstract

Due to the presence of atmosphere turbulence and the instability of airplane platform, deviations arise between the real track and the nominal one during synthetic aperture radar (SAR) data collection, which are referred to as motion errors. As for most known approaches (for example, precise tomography-and aperture-dependent algorithm), a reference range bin and reference azimuth time are assumed to perform the bulk rangeand azimuth-invariant compensation, leaving the range spreads and residual azimuth phase errors that impact the geometric fidelity of the final image. In this paper, a new fashion, entitled modified precise tomography- and aperture-dependent (MPTA), is proposed to make the complete corrections of the space-variant motion errors compensation. For the arbitrary residual motion errors and unsolved closed form of Doppler frequency-time relation, the numerical computation is developed along azimuth direction. Finally, we would present numerical experimental results characterizing the performance of the proposed MPTA.