Submit Manuscript
Peer Review
Editor Work
| Citation: | CHEN Jianlai, XIONG Yi, XU Gang, et al. Nonlinear trajectory synthetic aperture radar imaging and autofocus algorithm based on sub-image nonlinear chirp scaling[J]. Journal of Radars, 2022, 11(6): 1098–1109. doi: 10.12000/JR22171
|
Nonlinear Trajectory Synthetic Aperture Radar Imaging and Autofocus Algorithm Based on Sub-image Nonlinear Chirp Scaling
doi: 10.12000/JR22171
More Information-
Abstract
The radar echo signal may experience substantial two-dimensional spatial variance due to the nonlinear Synthetic Aperture Radar (SAR) trajectory. The traditional frequency-domain imaging algorithms based on the assumption of azimuth translational invariance are unsuitable for high-precision imaging of nonlinear trajectory SAR. Therefore, for nonlinear trajectory SAR imaging, the azimuth spatial variance of the echo signals is typically rectified using complex Nonlinear Chirp Scaling (NCS). However, when there are substantial motion errors, it cannot be effectively combined with the current autofocus algorithms considering the complexity of the algorithm due to too many NCS parameters. Thus, to address this issue, this study proposes a nonlinear trajectory SAR imaging and autofocus method according to the sub-image NCS, which can reduce the number of NCS parameters and ensure imaging accuracy; moreover, it is more conducive to the subsequent autofocus processing. The effectiveness of the suggested approach is confirmed by simulation and measured data processing. -
-
References
[1] 邢孟道, 林浩, 陈溅来, 等. 多平台合成孔径雷达成像算法综述[J]. 雷达学报, 2019, 8(6): 732–757. doi: 10.12000/JR19102XING Mengdao, LIN Hao, CHEN Jianlai, et al. A review of imaging algorithms in multi-platform-borne synthetic aperture radar[J]. Journal of Radars, 2019, 8(6): 732–757. doi: 10.12000/JR19102[2] 陈潇翔, 邢孟道. 基于空变运动误差分析的微波光子超高分辨SAR成像方法[J]. 雷达学报, 2019, 8(2): 205–214. doi: 10.12000/JR18121CHEN Xiaoxiang and XING Mengdao. An ultra-high-resolution microwave photonic-based SAR image method based on space-variant motion error analysis[J]. Journal of Radars, 2019, 8(2): 205–214. doi: 10.12000/JR18121[3] 李根, 马彦恒, 熊旭颖. 基于二维空变运动补偿的机动平台大斜视SAR稀疏自聚焦方法[J]. 电子与信息学报, 2021, 43(7): 1992–1999. doi: 10.11999/JEIT200456LI Gen, MA Yanheng, and XIONG Xuying. Sparse autofocus method for maneuvering platform high-squint SAR based on two-dimensional spatial-variant motion compensation[J]. Journal of Electronics &Information Technology, 2021, 43(7): 1992–1999. doi: 10.11999/JEIT200456[4] 施天玥, 刘惠欣, 刘衍琦, 等. 基于先验相位结构信息的双基SAR两维自聚焦算法[J]. 雷达学报, 2020, 9(6): 1045–1055. doi: 10.12000/JR20048SHI Tianyue, LIU Huixin, LIU Yanqi, et al. Bistatic synthetic aperture radar two-dimensional autofocus approach based on prior knowledge on phase structure[J]. Journal of Radars, 2020, 9(6): 1045–1055. doi: 10.12000/JR20048[5] CHEN Jianlai, XING Mengdao, YU Hanwen, et al. Motion compensation/autofocus in airborne synthetic aperture radar: A review[J]. IEEE Geoscience and Remote Sensing Magazine, 2022, 10(1): 185–206. doi: 10.1109/MGRS.2021.3113982[6] 别博文, 孙路, 邢孟道, 等. 基于局部直角坐标和子区域处理的弹载SAR频域成像算法[J]. 电子与信息学报, 2018, 40(8): 1779–1786. doi: 10.11999/JEIT171107BIE Bowen, SUN Lu, XING Mengdao, et al. A frequency-domain algorithm based on local Cartesian coordinate and subregion processing for missile-borne SAR imaging[J]. Journal of Electronics &Information Technology, 2018, 40(8): 1779–1786. doi: 10.11999/JEIT171107[7] CHEN Jianlai, ZHANG Junchao, JIN Yanghao, et al. Real-time processing of spaceborne SAR data with nonlinear trajectory based on variable PRF[J]. IEEE Transactions on Geoscience and Remote Sensing, 2022, 60: 5205212. doi: 10.1109/TGRS.2021.3067945[8] 李航, 刘文康, 孙光才, 等. 基于成像坐标系优化的中轨星载SAR成像方法[J]. 雷达学报, 2020, 9(5): 856–864. doi: 10.12000/JR20098LI Hang, LIU Wenkang, SUN Guangcai, et al. MEO SAR imaging based on imaging coordinate system optimization[J]. Journal of Radars, 2020, 9(5): 856–864. doi: 10.12000/JR20098[9] ASH J N. An autofocus method for backprojection imagery in synthetic aperture radar[J]. IEEE Geoscience and Remote Sensing Letters, 2012, 9(1): 104–108. doi: 10.1109/LGRS.2011.2161456[10] XIONG Yi, LIANG Buge, YU Hanwen, et al. Processing of bistatic SAR data with nonlinear trajectory using a controlled-SVD algorithm[J]. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2021, 14: 5750–5759. doi: 10.1109/JSTARS.2021.3084619[11] WU Junjie, LI Zhongyu, HUANG Yulin, et al. A generalized omega-K algorithm to process translationally variant bistatic-SAR data based on two-dimensional stolt mapping[J]. IEEE Transactions on Geoscience and Remote Sensing, 2014, 52(10): 6597–6614. doi: 10.1109/TGRS.2014.2299069[12] PRATS P, CAMARA DE MACEDO K A, REIGBER A, et al. Comparison of topography- and aperture-dependent motion compensation algorithms for airborne SAR[J]. IEEE Geoscience and Remote Sensing Letters, 2007, 4(3): 349–353. doi: 10.1109/LGRS.2007.895712[13] WONG F H, CUMMING I G, and NEO Y L. Focusing bistatic SAR data using the nonlinear chirp scaling algorithm[J]. IEEE Transactions on Geoscience and Remote Sensing, 2008, 46(9): 2493–2505. doi: 10.1109/TGRS.2008.917599[14] HUANG Lijia, QIU Xiaolan, HU Donghui, et al. Medium-earth-orbit SAR focusing using range Doppler algorithm with integrated two-step azimuth perturbation[J]. IEEE Geoscience and Remote Sensing Letters, 2015, 12(3): 626–630. doi: 10.1109/LGRS.2014.2353674[15] ZHANG Tianyi, DING Zegang, TIAN Weiming, et al. A 2-D nonlinear chirp scaling algorithm for high squint GEO SAR imaging based on optimal azimuth polynomial compensation[J]. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2017, 10(12): 5724–5735. doi: 10.1109/JSTARS.2017.2765353[16] ZENG Tao, LI Yinghe, DING Zegang, et al. Subaperture approach based on azimuth-dependent range cell migration correction and azimuth focusing parameter equalization for maneuvering high-squint-mode SAR[J]. IEEE Transactions on Geoscience and Remote Sensing, 2015, 53(12): 6718–6734. doi: 10.1109/TGRS.2015.2447393[17] LI Zhenyu, XING Mengdao, LIANG Yi, et al. A frequency-domain imaging algorithm for highly squinted SAR mounted on maneuvering platforms with nonlinear trajectory[J]. IEEE Transactions on Geoscience and Remote Sensing, 2016, 54(7): 4023–4038. doi: 10.1109/TGRS.2016.2535391[18] QIU Xiaolan, HU Donghui, and DING Chibiao. An improved NLCS algorithm with capability analysis for one-stationary BiSAR[J]. IEEE Transactions on Geoscience and Remote Sensing, 2008, 46(10): 3179–3186. doi: 10.1109/TGRS.2008.921569[19] WANG Zhigui, LIU Mei, AI Gengting, et al. Focusing of bistatic SAR with curved trajectory based on extended azimuth nonlinear chirp scaling[J]. IEEE Transactions on Geoscience and Remote Sensing, 2020, 58(6): 4160–4179. doi: 10.1109/TGRS.2019.2961562[20] CHEN Jianlai, ZHANG Junchao, YU Hanwen, et al. Blind NCS-based autofocus for airborne wide-beam SAR imaging[J]. IEEE Transactions on Computational Imaging, 2022, 8: 626–638. doi: 10.1109/TCI.2022.3194745[21] PRATS-IRAOLA P, SCHEIBER R, RODRIGUEZ-CASSOLA M, et al. On the processing of very high resolution spaceborne SAR data[J]. IEEE Transactions on Geoscience and Remote Sensing, 2014, 52(10): 6003–6016. doi: 10.1109/TGRS.2013.2294353[22] MOREIRA A and HUANG Yonghong. Airborne SAR processing of highly squinted data using a chirp scaling approach with integrated motion compensation[J]. IEEE Transactions on Geoscience and Remote Sensing, 1994, 32(5): 1029–1040. doi: 10.1109/36.312891 -
Proportional views
- Publishing Ethics
- Journal Insights
- Abstracting & Indexing
- Peer Review Policies
- Guide for Authors
- ISSN 2095-283X (Print)ISSN 2097-339X (Online)
- CN 10-1030/TN
- CODEN LXEUAO
About Journal
- Sponsor: China Radio Detection and Ranging Industry Association (CRIA)
- Phone: 010-58887062
- Email：radars@aircas.ac.cn
- Publisher: Leida Xuebao Bianjibu (Editorial office of the Journal of Radars)
Contacts Us
京ICP备20021838号-8
Supported by: Beijing Renhe Information Technology Co. Ltd
Export File
Citation
Format
Content
DownLoad:
- Figure 1. Geometric configuration of bistatic nonlinear trajectory SAR
- Figure 2. Flowchart of the proposed algorithm
- Figure 3. Schematic diagram for the second-order spatial-variant characteristic correction of quadratic error
- Figure 4. Change of residual spatial-variant phase with the number of sub images
- Figure 5. The simulation data processing results of the left edge target in the scene
- Figure 6. The simulation data processing results of the right edge target in the scene
- Figure 7. Analysis results of position offset
- Figure 8. Measured data processing results (The first and the third columns are the local enlarged images of the left and right edge scenes, respectively)