一种加速时域成像算法及其自聚焦方法

doi:10.3969/j.issn.1001-2400.2017.01.001

Abstract

Abstract:

The measurement accuracy of a navigation system is inadequate for airborne synthetic aperture radar (SAR). This may seriously degrade the image quality. In this paper, we propose an accelerated time domain (ATD) imaging algorithm combined with the autofocus method. By introducing the global pseudo polar coordinate (GPPC), we construct the Fourier transform pair (FTP) relationship. Then, the weighted least square phase gradient autofocus (WLS-PGA) algorithm is adopted to implement accurate phase error compensation. This method uses fast Fourier transform to implement sub-image fusions instead of time-consuming two-dimensional interpolation. Also, it has good compatibility with the high-accuracy autofocus algorithm to estimate the residual motion errors within the radar echoes and to obtain a well-focused image.

Key words: synthetic aperture radar(SAR), accelerated time domain(ATD) imaging algorithm, Fourier transform pair(FTP), weighted least square phase gradient autofocus(WLS-PGA)

ZENG Letian;LIANG Yi;LI Zhenyu;HUAI Yuanyuan;XING Mengdao. Accelerated time domain imaging algorithm and its autofocus approach[J].Journal of Xidian University, 2017, 44(1): 1-5+70.

References

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Accelerated time domain imaging algorithm and its autofocus approach

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