二面角的双基地散射特性分析
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摘要
二面角效应是高分辨率SAR图像非常重要的特征,其主要是建筑物的墙面和地面及其他人造物体形成的二面角造成的强反射。为了减小二面角的雷达散射截面积(Radar cross section,RCS),常用的技术是改变二面角的几何结构。双基地雷达是一种几何配置灵活的雷达,具有一定的反隐身能力。本文主要利用几何光学分析了不同张角二面角的散射特性及其SAR图像表现形式。针对二面角的多次散射问题,计算了散射次数和最终出射角度的通项公式,并给出了双基地条件下二面角RCS的定量计算公式。仿真结果表明,不同张角的二面角RCS和双基地雷达的几何结构密切相关,在特定的双基地雷达几何配置下,二面角在双基地SAR图像中表现为角点处的强点。
Dihedral corner effect is an important characteristic of SAR images,especially for the strong scatters generated by buildings and other human-made objects.Changing the opening angle of the dihedrals is a popular method to reduce radar cross section(RCS).Bistatic radar,which has flexible geometric configuration,is a good way to detect stealth targets.This paper analyzes the bistatic scattering characteristic of different dihedral corner reflectors using geometrical optics methods.As for the multiple scattering effect in the dihedral corners,the general term formula is given to describe the multiple scattering times and echo angles.Besides,the RCS calculation formula of dihedral corner is extended to bistatic condition.Both theory and simulation results show that bistatic radar has the ability to detect changed dihedral corners and its bistatic SAR image formation is a strong point at the corner point under a certain bistatic angle.
Dihedral corner effect is an important characteristic of SAR images,especially for the strong scatters generated by buildings and other human-made objects.Changing the opening angle of the dihedrals is a popular method to reduce radar cross section(RCS).Bistatic radar,which has flexible geometric configuration,is a good way to detect stealth targets.This paper analyzes the bistatic scattering characteristic of different dihedral corner reflectors using geometrical optics methods.As for the multiple scattering effect in the dihedral corners,the general term formula is given to describe the multiple scattering times and echo angles.Besides,the RCS calculation formula of dihedral corner is extended to bistatic condition.Both theory and simulation results show that bistatic radar has the ability to detect changed dihedral corners and its bistatic SAR image formation is a strong point at the corner point under a certain bistatic angle.
引文
[1]Zeng T,Ao D,Hu C,et al.Multiangle BSAR imaging based on BeiDou-2navigation satellite system:Experiments and preliminary results[J].Geoscience and Remote Sensing,IEEE Transactions on,2015,53(10):5760-5773.
[2]Martinsek D,Goldstein R.Bistatic radar experiment[C]//EUSAR'98-European Conference on Synthetic Aperture Radar.Friedrichshafen,Germany:[s.n.],1998:31-34.
[3]Sanz-Marcos J,Lopez-Dekker P,Mallorqui J J,et al.SABRINA:A SAR bistatic receiver for interferometric applications[J].IEEE Geoscience and Remote Sensing Letters,2007,4(2):307-311.
[4]Ender J H G.Signal theoretical aspects of bistatic SAR[C]//International Geoscience and Remote Sensing Symposium.Toulouse,France:IEEE,2003,3:1438-1441.
[5]Zeng T,Wang R,Li F,et al.A modified nonlinear chirp scaling algorithm for spaceborne/stationary bistatic SAR based on series reversion[J].IEEE Transactions on Geoscience and Remote Sensing,2013,51(5):3108-3118.
[6]Qiu X,Hu D,Ding C.An improved NLCS algorithm with capability analysis for one-stationary BiSAR[J].IEEE Transactions on Geoscience and Remote Sensing,2008,46(10):3179-3186.
[7]郭宝锋,尚朝轩,高梅国,等.机动目标双基地ISAR越距离单元徙动校正算法[J].数据采集与处理,2014,29(4):562-569.Guo Baofeng,Shang Chaoxuan,Gao Meiguo,et al.Correction algorithm of migration through resolution cells in bistatic ISAR of maneuvering target[J].Journal of Data Acquisition and Processing,2014,29(4):562-569.
[8]何友,张财生.无源双基地雷达广义相参检测性能分析[J].数据采集与处理,2014,29(4):486-495.He You,Zhang Caisheng.Generalized coherent detection performance analysis for passive bistatic radar[J].Journal of Data Acquisition and Processing,2014,29(4):486-495.
[9]徐旭宇,牛朝阳,李小波,等.空间色噪声环境下双基地MIMO雷达多目标角度估计和互耦自校正[J].数据采集与处理,2014,29(5):735-742.Xu Xuyu,Niu Chaoyang,Li Xiaobo,et al.Multi target angle estimation and mutual coupling self calibration of bistatic MIMO radar in spatial colored noise[J].Journal of Data Acquisition and Processing,2014,29(5):735-742.
[10]Jackson J A.Analytic physical optics solution for bistatic,3Dscattering from a dihedral corner reflector[J].Antennas and Propagation,IEEE Transactions on,2012,60(3):1486-1495.
[11]Brunner D,Bruzzone L,Ferro A,et al.Analysis of the double bounce scattering mechanism of buildings in VHR SAR data[C]//Proc SPIE Conf Image Signal Process,Remote Sens XIV.Cardiff,UK:SPIE,2008:15-18.
[12]Yongmei J,Diannong L.A physics-based UWB FOPEN SAR man-made target detector[C]//Signal Processing Proceedings,ICSP′98,1998Fourth International Conference on.Beijing:IEEE,1998:1465-1468.
[13]范菊红,王月清.二面角反射器的RCS特性分析[J].舰船电子工程,2006(2):148-150.Fan Juhong,Wang Yueqing.Analysis of RCS characteristic of dihedral corner reflectors[J].Ship Electronic Engineering,2006(2):148-150.
[14]杨志国,王亮,黄晓涛,等.UWB SAR目标检测中的二面角模型改进[J].现代雷达,2007,29(11):64-67.Yang Zhiguo,Wang Liang,Huang Xiaotao,et al.Improvement of dihedral angle model in UWB SAR target detection[J].Modern Radar,2007,29(11):64-67.
[15]Burkholder R J,Gupta I J,Johnson J T.Comparison of monostatic and bistatic radar images[J].Antennas and Propagation Magazine,IEEE,2003,45(3):41-50.
[16]曾涛.双基地合成孔径雷达发展现状与趋势分析[J].雷达学报,2013,2(4):329-341.Zeng Tao.Bistatic SAR:State of the art and development trend[J].Journal of Radars,2013,2(4):329-341.
[17]洪文.圆迹SAR成像技术研究进展[J].雷达学报,2012,1(2):124-135.Hong Wen.Progress in circular SAR imaging technique[J].Journal of Radars,2012,1(2):124-135.
[18]Ertin E,Austin C D,Sharma S,et al.GOTCHA experience report:Three-dimensional SAR imaging with complete circular apertures[C]//Defense and Security Symposium,International Society for Optics and Photonics.Bellingham:SPIE,2007:656802-656802-12.
[19]Zeng Tao,Ao Dongyang,Hu Cheng,et al.Comparison between monostatic and bistatic SAR image based on spatial spectrum analysis[C]//IET International Radar Conference 2015.Xi′an:IET,2015:1-6.
[20]Rigling B D,Moses R L.GTD-based scattering models for bistatic SAR[C]//Defense and Security,International Society for Optics and Photonics.Bellingham:SPIE,2004:208-219.
[21]Griesser T,Balanis C A.Dihedral corner reflector backscatter using higher order reflections and diffractions[J].Antennas and Propagation,IEEE Transactions on,1987,35(11):1235-1247.
[22]Knott E.RCS reduction of dihedral corners[J].Antennas and Propagation,IEEE Transactions on,1977,25(3):406-409.
[23]Gordon W B.Far-field approximations to the Kirchoff-helmholtz representations of scattered fields[J].Antennas and Propagation,IEEE Transactions on,1975,23(4):590-592.
[24]Ulander L M H,Martin T.Bistatic ultra-wideband SAR for imaging of ground targets under foliage[C]//Radar Conference,2005IEEE International.Virginia:IEEE,2005:419-423.
[2]Martinsek D,Goldstein R.Bistatic radar experiment[C]//EUSAR'98-European Conference on Synthetic Aperture Radar.Friedrichshafen,Germany:[s.n.],1998:31-34.
[3]Sanz-Marcos J,Lopez-Dekker P,Mallorqui J J,et al.SABRINA:A SAR bistatic receiver for interferometric applications[J].IEEE Geoscience and Remote Sensing Letters,2007,4(2):307-311.
[4]Ender J H G.Signal theoretical aspects of bistatic SAR[C]//International Geoscience and Remote Sensing Symposium.Toulouse,France:IEEE,2003,3:1438-1441.
[5]Zeng T,Wang R,Li F,et al.A modified nonlinear chirp scaling algorithm for spaceborne/stationary bistatic SAR based on series reversion[J].IEEE Transactions on Geoscience and Remote Sensing,2013,51(5):3108-3118.
[6]Qiu X,Hu D,Ding C.An improved NLCS algorithm with capability analysis for one-stationary BiSAR[J].IEEE Transactions on Geoscience and Remote Sensing,2008,46(10):3179-3186.
[7]郭宝锋,尚朝轩,高梅国,等.机动目标双基地ISAR越距离单元徙动校正算法[J].数据采集与处理,2014,29(4):562-569.Guo Baofeng,Shang Chaoxuan,Gao Meiguo,et al.Correction algorithm of migration through resolution cells in bistatic ISAR of maneuvering target[J].Journal of Data Acquisition and Processing,2014,29(4):562-569.
[8]何友,张财生.无源双基地雷达广义相参检测性能分析[J].数据采集与处理,2014,29(4):486-495.He You,Zhang Caisheng.Generalized coherent detection performance analysis for passive bistatic radar[J].Journal of Data Acquisition and Processing,2014,29(4):486-495.
[9]徐旭宇,牛朝阳,李小波,等.空间色噪声环境下双基地MIMO雷达多目标角度估计和互耦自校正[J].数据采集与处理,2014,29(5):735-742.Xu Xuyu,Niu Chaoyang,Li Xiaobo,et al.Multi target angle estimation and mutual coupling self calibration of bistatic MIMO radar in spatial colored noise[J].Journal of Data Acquisition and Processing,2014,29(5):735-742.
[10]Jackson J A.Analytic physical optics solution for bistatic,3Dscattering from a dihedral corner reflector[J].Antennas and Propagation,IEEE Transactions on,2012,60(3):1486-1495.
[11]Brunner D,Bruzzone L,Ferro A,et al.Analysis of the double bounce scattering mechanism of buildings in VHR SAR data[C]//Proc SPIE Conf Image Signal Process,Remote Sens XIV.Cardiff,UK:SPIE,2008:15-18.
[12]Yongmei J,Diannong L.A physics-based UWB FOPEN SAR man-made target detector[C]//Signal Processing Proceedings,ICSP′98,1998Fourth International Conference on.Beijing:IEEE,1998:1465-1468.
[13]范菊红,王月清.二面角反射器的RCS特性分析[J].舰船电子工程,2006(2):148-150.Fan Juhong,Wang Yueqing.Analysis of RCS characteristic of dihedral corner reflectors[J].Ship Electronic Engineering,2006(2):148-150.
[14]杨志国,王亮,黄晓涛,等.UWB SAR目标检测中的二面角模型改进[J].现代雷达,2007,29(11):64-67.Yang Zhiguo,Wang Liang,Huang Xiaotao,et al.Improvement of dihedral angle model in UWB SAR target detection[J].Modern Radar,2007,29(11):64-67.
[15]Burkholder R J,Gupta I J,Johnson J T.Comparison of monostatic and bistatic radar images[J].Antennas and Propagation Magazine,IEEE,2003,45(3):41-50.
[16]曾涛.双基地合成孔径雷达发展现状与趋势分析[J].雷达学报,2013,2(4):329-341.Zeng Tao.Bistatic SAR:State of the art and development trend[J].Journal of Radars,2013,2(4):329-341.
[17]洪文.圆迹SAR成像技术研究进展[J].雷达学报,2012,1(2):124-135.Hong Wen.Progress in circular SAR imaging technique[J].Journal of Radars,2012,1(2):124-135.
[18]Ertin E,Austin C D,Sharma S,et al.GOTCHA experience report:Three-dimensional SAR imaging with complete circular apertures[C]//Defense and Security Symposium,International Society for Optics and Photonics.Bellingham:SPIE,2007:656802-656802-12.
[19]Zeng Tao,Ao Dongyang,Hu Cheng,et al.Comparison between monostatic and bistatic SAR image based on spatial spectrum analysis[C]//IET International Radar Conference 2015.Xi′an:IET,2015:1-6.
[20]Rigling B D,Moses R L.GTD-based scattering models for bistatic SAR[C]//Defense and Security,International Society for Optics and Photonics.Bellingham:SPIE,2004:208-219.
[21]Griesser T,Balanis C A.Dihedral corner reflector backscatter using higher order reflections and diffractions[J].Antennas and Propagation,IEEE Transactions on,1987,35(11):1235-1247.
[22]Knott E.RCS reduction of dihedral corners[J].Antennas and Propagation,IEEE Transactions on,1977,25(3):406-409.
[23]Gordon W B.Far-field approximations to the Kirchoff-helmholtz representations of scattered fields[J].Antennas and Propagation,IEEE Transactions on,1975,23(4):590-592.
[24]Ulander L M H,Martin T.Bistatic ultra-wideband SAR for imaging of ground targets under foliage[C]//Radar Conference,2005IEEE International.Virginia:IEEE,2005:419-423.