Bistatic sliding-spotlight synthetic aperture radar (SAR) can not only maintains the flexibility, reliability and stability of the bistatic SAR, but also produce high-resolution image pairs with great potential for observation and mapping. This mode should consider both characteristics of bistatic imaging and a significant increase in Doppler bandwidth. In this paper, the Doppler characteristics of the target in bistatic sliding-spotlight SAR system are analyzed, then, a two-step imaging algorithm based on hyperbolic equivalent method is proposed by combining the bistatic imaging algorithm with the spectrum analysis method. At the same time, for the degradation of the focus quality caused by the error of hyperbolic equivalent model, the model error compensation method is proposed, and the complete algorithm processing flow is given. Finally, the proposed algorithm is verified by simulation experiments.
XIANG Jianbing
,
Lü Xiaolei
,
FU Xikai
. Two-step imaging algorithm of bistatic sliding-spotlight SAR based on hyperbolic equivalent method[J]. Journal of University of Chinese Academy of Sciences, 2021
, 38(4)
: 511
-518
.
DOI: 10.7523/j.issn.2095-6134.2021.04.010
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