Wide Band and Wide Azimuth Beam Effect on High-resolution Synthetic Aperture Radar Radiometric Calibration
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摘要: 无源角反射器和有源定标器是SAR辐射定标的常用人造参考点目标,随着大量新体制、新模式高分辨率SAR系统的涌现,大距离带宽和宽方位波束都对传统观念中参考目标雷达截面积(RCS)近似恒定的假设提出挑战.该文借助FEKO电磁仿真软件获取目标RCS随频带和方位角的变化关系,结合高分辨率SAR点目标仿真,通过点目标能量提取,定量地分析参考目标RCS的频带或方位角相关性对辐射定标的影响.仿真结果表明在Ku波段相对带宽超过10%或方位波束宽度超过20时,上述因素带来的影响超过0.2 dB,必须在实际数据处理中加以校正.
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关键词:
- SAR辐射定标 /
- 雷达截面积(RCS) /
- 参考目标 /
- 大距离带宽和宽方位波束 /
- FEKO
Abstract: Passive corner reflectors and active transponders are often used as man-made reference targets in Synthetic Aperture Radar (SAR) radiometric calibration, With the emergence of new radar systems and the increasing demand for greater accuracy, wide-band and wide-beam radars challenge the hypothesis that the Radar Cross Section (RCS) of reference targets is constant. In this study, the FEKO electromagnetic simulation software is used to obtain the change curve of the target RCS as a function of frequency and aspect angle while incorporating high-resolution point-target SAR simulation, and quantitatively analyzing the effect of the modulation effect on SAR images. The simulation results suggest that the abovementioned factors affect the SAR calibration by more than 0.2 dB within a fractional bandwidth greater than 10% or azimuth beam width of more than 20, which must be corrected in the data processing.-
Key words:
- SAR calibration /
- Radar Cross Section (RCS) /
- Reference target /
- Wide-band and wide-beam /
- FEKO
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[1] Curlander J C. 合成孔径雷达系统与信号处理[M]. 北京: 电 子工业出版社, 2006: 217-220. Curlander J C. Synthetic Aperture Radar: Systems and Signal Processing[M]. Beijing: Publishing House of Electronics Industry, 2006: 217-220. [2] 李震, 廖静娟, 等. 合成孔径雷达地表参数反演模型与方法[M]. 北京: 科学出版社, 2011: 24-33. Li Zhen, Liao Jing-juan, et al.. Synthetic Aperture Radar Surface Parameters Inversion Model and Method[M]. Beijing: Publishing House of Science, 2011: 24-33. [3] Khalid E D, Peter M, Desmond P, et al.. Understanding the significance of radiometric calibration for SAR imagery[C]. Canadian Conference on Electrical and Computer Engineering, Toronto, Canada, 2014: 1-6. [4] Freeman A. SAR calibration: an overview[J]. IEEE Transactions on Geoscience and Remote Sensing, 1992, 30(6): 1107-1123. [5] Gray A L, Paris W V, and Charles E L. Synthetic aperture radar calibration using reference reflectors[J]. IEEE Transactions on Geoscience and Remote Sensing, 1990, 28(3): 374-382. [6] Ulander L M H. Accuracy of using point targets for SAR calibration[J]. IEEE Transactions on Aerospace and Electronic Systems, 1991, 27(1): 139-148. [7] 邹鲲. 低频UWB-SAR校准技术研究[D]. [博士论文], 国防科学 技术大学, 2005. Zou Kun. Research on low frequency UWB-SAR calibration technique[D]. [Ph.D. dissertation], National University of Defense Technology, 2005. [8] 林新越. 高 分辨率SAR参考点目标辐射特性分析与校正方法 研究[D]. [硕士论文], 中国科学院电子学研究所, 2010. Lin Xin-yue. Analysis and calibration method for radiometric characteristics of reference targets in high resolution SAR systems[D]. [Master dissertation], Institute of Electronics, Chinese Academy of Sciences, 2010. [9] Bjorn J D, Philipp R L, Matthias J, et al.. Reference target correction based on point-target SAR simulation[J]. IEEE Transactions on Geoscience and Remote Sensing, 2012, 50(3): 951-958. [10] Bjorn J D and Marco S. The radiometric measurement quantity for SAR images[J]. IEEE Transactions on Geoscience and Remote Sensing, 2013, 51(12): 5307-5313. [11] 黄培康, 殷红成, 许小剑. 雷达目标特性[M]. 北京: 电子工业出 版社, 2010: 16-19. Huang Pei-kang, Yin Hong-cheng, and Xu Xiao-jian. Radar Target Characteristics[M]. Beijing: Publishing House of Electronics Industry, 2010: 16-19. [12] Griesser T and Balanis A. Backscatter analysis of dihedral corner reflectors using physical optics and the physical theory of diffraction[J]. IEEE Transactions on Antennas and Propagation, 1987, 35(10): 1137-1147. [13] Sarabandi K and Chiu T. Optimum corner reflectors for calibration of imaging radars[J]. IEEE Transactions on Antennas and Propagation, 1996, 44(10): 1348-1361. [14] 林新越, 洪峻, 明峰. 高分辨率SAR参考点目标频带调制效应 的校正方法[J]. 国外电子测量技术, 2010, 29(4): 32-36. Lin Xin-yue, Hong Jun, and Ming Feng. A calibration method for frequency modulation of reference targets in high resolution SAR systems[J]. Foreign Electronic Measurement Technology, 2010, 29(4): 32-36. [15] Cumming I G and Wong F H. 合成孔径雷达成像算法与 实现[M]. 北京: 电子工业出版社, 2007: 38-41. Cumming I G and Wong F H. Digital Processing of Synthetic Aperture Radar Data: Algorithms and Implementation[M]. Beijing: Publishing House of Electronics Industry, 2007: 38-41.
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