电子与控制

结合视线方向运动补偿的滑动聚束SAR子孔径成像算法

  • 杨鸣冬 ,
  • 朱岱寅
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  • 南京航空航天大学 电子信息工程学院 雷达成像与微波光子技术教育部重点实验室, 南京 210016
杨鸣冬,男,博士研究生。主要研究方向:合成孔径雷达成像,高精度运动补偿。Tel:025-84896491-12501,E-mail:yangmd@nuaa.edu.cn;朱岱寅,男,博士,教授,博士生导师。主要研究方向:合成孔径雷达信号处理。Tel:025-84892410,E-mail:zhudy@nuaa.edu.cn

收稿日期: 2015-03-17

  修回日期: 2015-05-29

  网络出版日期: 2015-06-03

基金资助

国家自然科学基金(61301210);航空科学基金(20142052021);江苏省自然科学基金(BK20130815);江苏省博士后科研资助计划(1301027B);江苏省高校优势学科建设工程资助项目

An imaging algorithm for sliding spotlight SAR using subaperture with line-of-sight motion compensation

  • YANG Mingdong ,
  • ZHU Daiyin
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  • Key Laboratory of Radar Imaging and Microwave Photonics, Ministry of Education, College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China

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

摘要

滑动聚束合成孔径雷达(SAR)是一种新兴的成像模式,既可以提高方位向分辨率又能够扩展成像范围。其数据处理时需要考虑两个关键问题:一是系统脉冲重复频率(PRF)不足,方位向信号发生混叠;二是合成孔径长度的增加使运动误差的影响更为突出,运动补偿(MOCO)精度要求提高。基于子孔径技术,提出了一种改进的高分辨率成像算法。划分子孔径克服了PRF不足的问题;子孔径数据处理采用结合视线(LOS)方向运动补偿的Omega-K算法,实现更高精度的运动补偿,提高了聚焦质量。最终的方位向分辨率达到0.1 m,具有实际工程应用价值。点目标仿真和实测数据处理验证了算法的有效性。

本文引用格式

杨鸣冬 , 朱岱寅 . 结合视线方向运动补偿的滑动聚束SAR子孔径成像算法[J]. 航空学报, 2016 , 37(3) : 984 -996 . DOI: 10.7527/S1000-6893.2015.0159

Abstract

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.

参考文献

[1] LANARI R, ZOFFOLI S, SANSOSTI E, et al. New approach for hybrid strip-map/spotlight SAR data focusing[J]. IEE Proceedings-Radar, Sonar and Navigation, 2001, 148(6):363-372.
[2] BRENNER A R. Ultra-high resolution airborne SAR imaging of vegetation and man-made objects based on 40% relative bandwidth in X-band[C]//2012 IEEE International Geoscience and Remote Sensing Symposium(IGARSS). Piscataway, NJ:IEEE Press, 2012:7397-7400.
[3] MITTERMAYER J, WOLLSTADT S, PRATS P, et al. The TerraSAR-X staring spotlight mode concept[J]. IEEE Transactions on Geoscience and Remote Sensing, 2014, 52(6):3695-3706.
[4] MOREIRA A, MITTERMAYER J, SCHEIBER R. Extended chirp scaling algorithm for air-and spaceborne SAR data processing in stripmap and ScanSAR imaging modes[J]. IEEE Transactions on Geoscience and Remote Sensing, 1996, 34(5):1123-1136.
[5] MITTERMAYER J, MOREIRA A, LOFFELD O. Spotlight SAR data processing using the frequency scaling algorithm[J]. IEEE Transactions on Geoscience and Remote Sensing, 1999, 37(5):2198-2214.
[6] LANARI R, TESAURO M, SANSOSTI E, et al. Spotlight SAR data focusing based on a two-step processing approach[J]. IEEE Transactions on Geoscience and Remote Sensing, 2001, 39(9):1993-2004.
[7] ZHU D Y, YE S H, ZHU Z D. Polar format algorithm using chirp scaling for spotlight SAR image formation[J]. IEEE Transactions on Aerospace and Electronic Systems, 2008, 44(4):1433-1448.
[8] CAFFORIO C, PRATI C, ROCCA F. SAR data focusing using seismic migration techniques[J]. IEEE Transactions on Aerospace and Electronic Systems, 1991, 27(2):194-206.
[9] MITTERMAYER J, LORD R, BORNER E. Sliding spotlight SAR processing for TerraSAR-X using a new formulation of the extended chirp scaling algorithm[C]//2003 IEEE International Geoscience and Remote Sensing Symposium(IGARSS). Piscataway, NJ:IEEE Press, 2003:1462-1464.
[10] PRATS P, SCHEIBER R, MITTERMAYER J, et al. Processing of sliding spotlight and TOPS SAR data using baseband azimuth scaling[J]. IEEE Transactions on Geoscience and Remote Sensing, 2010, 48(2):770-780.
[11] BELCHER D P, BAKER C J. High resolution processing of hybrid strip-map/spotlight mode SAR[J]. IEE Proceedings-Radar, Sonar and Navigation, 1996, 143(6):366-374.
[12] WANG R, LOFFELD O, NIES H, et al. Focusing spaceborne/airborne hybrid bistatic SAR data using wavenumber-domain algorithm[J]. IEEE Transactions on Geoscience and Remote Sensing, 2009, 47(7):2275-2283.
[13] SUN G C, XING M D, XIA X G, et al. Beam steering SAR data processing by a generalized PFA[J]. IEEE Transactions on Geoscience and Remote Sensing, 2013, 51(8):4366-4377.
[14] SUN G C, XING M D, WANG Y, et al. Sliding spotlight and TOPS SAR data processing without subaperture[J]. IEEE Geoscience and Remote Sensing Letters, 2011, 8(6):1036-1040.
[15] XU W, DENG Y K, HUANG P P, et al. Full-aperture SAR data focusing in the spaceborne squinted sliding-spotlight mode[J]. IEEE Transactions on Geoscience and Remote Sensing, 2013, 52(8):4596-4607.
[16] WU Y F, SUN G C, XIA X G, et al. An azimuth frequency non-linear chirp scaling(FNCS) algorithm for TOPS SAR imaging with high squint angle[J]. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2014, 7(1):213-221.
[17] HE F, CHEN Q, DONG Z, et al. Processing of ultrahigh-resolution spaceborne sliding spotlight SAR data on curved orbit[J]. IEEE Transactions on Aerospace and Electronic Systems, 2013, 49(2):819-839.
[18] 毛新华, 朱岱寅, 朱兆达. 复杂航迹和起伏地形条件下机载聚束SAR空变运动补偿[J]. 航空学报, 2012, 33(4):744-754. MAO X H, ZHU D Y, ZHU Z D. Space-variant motion compensation for airborne spotlight SAR under complicated flight path and rugged terrain[J]. Acta Aeronautica et Astronautica Sinica, 2012, 33(4):744-754(in Chinese).
[19] 宋伟, 朱岱寅, 叶少华. 基于数值计算的机载SAR空变运动补偿算法[J]. 航空学报, 2015, 36(2):625-632. SONG W, ZHU D Y, YE S H. Airborne SAR space-variant motion compensation algorithm based on numerical calculation[J]. Acta Aeronautica et Astronautica Sinica, 2015, 36(2):625-632(in Chinese).
[20] DING Z G, LIU L S, ZENG T, et al. Improved motion compensation approach for squint airborne SAR[J]. IEEE Transactions on Geoscience and Remote Sensing, 2013, 51(8):4378-4387.
[21] 曾乐天, 邢孟道, 陈士超. 基于窄波束和平地假设的运动补偿方向研究[J]. 电子与信息学报, 2014, 36(10):2464-2468. ZENG L T, XING M D, CHEN S C. The research on the direction of motion compensation according to the narrow beam and flat earth hypothesis[J]. Journal of Electronics & Information Technology, 2014, 36(10):2464-2468(in Chinese).
[22] CUMMING I G, WONG F H. Digital processing of synthetic aperture radar:Algorithms and implementation[M]. Boston:Artech House, 2005:176-177.
[23] FORNARO G. Trajectory deviations in airborne SAR:Analysis and compensation[J]. IEEE Transactions on Aerospace and Electronic Systems, 1999, 35(3):997-1009.

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