| 摘要: |
| 高轨SAR覆盖范围广、轨道回归周期短，具有探测动目标的优势。由于高轨SAR轨道高度高，斜视成像模式下几何关系呈现非平直特点，低轨SAR平直成像几何下的影响分析模型并不能直接适用于高轨情况。建立高轨SAR非平直斜视成像几何，利用等距离等多普勒方程推导得到匀速运动目标成像位置偏移、二次相位误差、三次相位误差的解析表达式，分析目标运动对成像偏移、散焦造成的影响，并与平直成像几何下的运动成像影响进行对比分析。基于动目标探测角度给出仿真高轨SAR雷达参数和轨道参数，通过仿真分析，验证了成像影响理论推导的正确性。 |
| 关键词: 高轨SAR 运动目标 非平直斜视成像 运动影响 |
| DOI：10.3969/j.issn.1672-2337.2018.05.006 |
| 分类号:TN958 |
| 基金项目: |
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| Modeling and Analysis of Target Motion Influence on GEO SAR Based on Non-Straight Squint Imaging Geometry |
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HU Zheying，HUANG Lijia，HU Wenlong，LU Xiaojun
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1.Key Laboratory of Technology in Geo-Spatial Information Processing and Application System，Chinese Academy of Sciences，Beijing 100190，China;2.Institute of Electronics，Chinese Academy of Sciences，Beijing 100190，China;3.University of Chinese Academy of Sciences，Beijing 100049，China;4.China International Engineering Consulting Corporation，Beijing 100048，China
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| Abstract: |
| Geosynchronous SAR (GEO SAR) is capable of detecting moving target based on its wide swath and short return period.Because of the high orbit of GEO SAR，the geometry model under squint imaging mode is non-straight，and the motion influence model based on straight geometry of low earth orbit SAR is inapplicable to GEO SAR.Therefore，the model of GEO SAR non-straight squint imaging geometry is built.And then，based on equal range-Doppler equation，the analytic expressions of imaging displacement，quadratic phase error and cubic phase error of uniform moving target are deduced.The influences of target motion on imaging displacement and defocusing are analyzed.A comparison with the motion influence of straight imaging geometry is made.From the aspect of moving target detection，the radar parameters and orbital parameters of GEO SAR are obtained.The correctness of the imaging influence theory is verified by simulation analysis. |
| Key words: geosynchronous SAR(GEO SAR) moving target non-straight squint imaging motion influence |
