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An imaging algorithm for sliding spotlight SAR using subaperture with line-of-sight motion compensation
Received date: 2015-03-17
Revised date: 2015-05-29
Online published: 2015-06-03
Supported by
National Natural Science Foundation of China(61301210);Aeronautical Science Foundation of China(20142052021);Natural Science Foundation of Jiangsu Province(BK20130815);Jiangsu Planned Projects for Postdoctoral Research Funds(1301027B);A Project Founded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
Sliding spotlight synthetic aperture radar(SAR) is a rising imaging mode, whose azimuth resolution is higher and imaged area is greater. When processing data, two key problems should be considered. Firstly, system's pulse repetition frequency(PRF) is always insufficient, which makes the azimuth signal folding. Secondly, the effect of motion error enhances because of longer synthetic aperture, consequently the accuracy of motion compensation(MOCO) should be increased. This paper presents a modified high-resolution imaging scheme based on subaperture. Subaperture method is used to overcome the problem that PRF is insufficient. Meanwhile, processing of subaperture data chooses Omega-K algorithm with line-of-sight(LOS) motion compensation to implement high-precision motion compensation, improving focused quality. The presented algorithm can attain 0.1 m azimuth resolution and has the value of practice. Simulations with point targets and processing of real data are used to confirm the validity of the proposed algorithm.
YANG Mingdong , ZHU Daiyin . An imaging algorithm for sliding spotlight SAR using subaperture with line-of-sight motion compensation[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2016 , 37(3) : 984 -996 . DOI: 10.7527/S1000-6893.2015.0159
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