随机粗糙面上解决低频崩溃问题的电磁散射研究
|
摘要
本文用线性滤波法模拟了二维随机粗糙表面,介绍了新型的积分方程增量型电场积分方程(AEFIE)。并用新型的积分方程来解决计算随机粗糙面的RCS面临的低频崩溃问题。采用商业FEKO软件中矩量法(MOM)对随机粗糙面双站散射系数σ进行计算时,由于低频下剖分尺寸远小于波长,产生低频崩溃问题,使得低频求解中得不到精确的解,导致计算时间过长以及计算的散射系数误差较大等情况的产生。本文又采用了自编程软件的AEFIE并用多层快速多极子法加速与商业FEKO软件中传统多层快速多极子算法(MLFMA)对随机粗糙面双站散射系数σ进行计算与对比,不仅表明了AEFIE方法计算随机粗糙面散射系数σ的准确性,也突出了AEFIE方法用多层快速多极子算法加速后占用内存更少以及更高效的特性。同时也验证了均方根高度和相关长度的变化对RCS的影响,最后得出结论。
In this paper,a two-dimensional random rough surface is simulated by the linear filtering method,and a new augmented electric field integral equation(AEFIE) is introduced. A new type of integral equation is also used to solve the low-frequency collapse problem of RCS. When calculating the birefringence σ of a random rough surface by using the method of moment analysis(MOM) in the commercial FEKO software,the problem of low-frequency collapse arises because the sub-wavelength size is much smaller than the wavelength in the low frequency,resulting in lack of memory in the computer,calculation time is too long and the calculated scattering coefficient error is larger and so on. In this paper,the self-programming software AEFIE method and the multi-layer fast multipole algorithm(MLFMA) in the commercial FEKO software are used to calculate and compare the two-station scattering coefficient σ of the random rough surface. It not only shows that the AEFIE method can calculate the random rough surface scattering coefficient σ Accuracy,but also highlights the AEFIE method occupies less memory and more efficient features. At the same time,we also verify the influence of the root mean square height and the correlation length on the RCS,and finally conclude.
In this paper,a two-dimensional random rough surface is simulated by the linear filtering method,and a new augmented electric field integral equation(AEFIE) is introduced. A new type of integral equation is also used to solve the low-frequency collapse problem of RCS. When calculating the birefringence σ of a random rough surface by using the method of moment analysis(MOM) in the commercial FEKO software,the problem of low-frequency collapse arises because the sub-wavelength size is much smaller than the wavelength in the low frequency,resulting in lack of memory in the computer,calculation time is too long and the calculated scattering coefficient error is larger and so on. In this paper,the self-programming software AEFIE method and the multi-layer fast multipole algorithm(MLFMA) in the commercial FEKO software are used to calculate and compare the two-station scattering coefficient σ of the random rough surface. It not only shows that the AEFIE method can calculate the random rough surface scattering coefficient σ Accuracy,but also highlights the AEFIE method occupies less memory and more efficient features. At the same time,we also verify the influence of the root mean square height and the correlation length on the RCS,and finally conclude.
引文
[1]D.R.Wilton and A.W.Glisson,O improving the electric field integral equation at low frequencies,URSI Radio Science Meeting Digest,Los Angeles,CA,June 1981,pp.24
[2]逯贵祯,王宝发.高斯随机粗糙表面的电磁散射研究[J].电子学报,2002,30(6):907-908.
[3]Thorsos E.The validity of the Kirchhoff approximation for rough surface scattering using a Gaussian roughness spectrum[J].1/++7 J Acoust Soc Am,1988,83(1):78-91.
[4]Wang X,Wang C F,Gan Y B.Electromagnetic scattering from a circular target above or below rough surface[J].Progress in Electromagnetics Research,2003,40:207-227.
[5]Kuga Y,Phu P.Experimental studies of millimeterwave scattering in discrete random media and from rough surfaces[J].Progress in Electromagnetics Research,1996,14:37-38.
[6]闫沛文,童创明,姬伟杰.SM FSIA/CA G快速计算二维分形粗糙面的电磁散射特性[J].系统工程与电子技术,2009,31(9):2117-2120.
[7]田炜,任新成.一维指数型粗糙土壤表面电磁散射的矩量法研究[J].科学技术与工程,2011,11(10):2211-2214.
[8]郭立新,王蕊,吴振森.随机粗糙面散射的基本理论与方法[M].北京:科学出版社,2009:1-60.
[9]Bass.Wave Scattering from Statistically Rough Surfaces[C].Oxford:Pergamum,1979.
[10]A.Ishimaru,and J S.Chen.Scattering from very rough surfaces based on the modified second-order Kirchhoff approximation with angular and propagation shadowing[M].J.Acoust.Soc.Am,1990:1877-1883.
[11]Bruce N C.Multiple scatter of vector electromagnetic waves from rough metal surfaces with infinite slopes using the Kirchhoff approximation[J].Waves in Random and Complex Media,2011,21(2):362-377.
[12]W.Wu,A.W.Glisson and D.Kajfez.,A Comparison of Two Low-frequency Formulations for the Electric Field Integral Equation,Proceedings of the 10th Annual Review of Progress in Applied Computational Electromagnetics,Monterey,California,Vol.2,pp 484-491.
[13]J.S.Zhao,W.C.Chew,Integral equation solution of Maxwell's equations from zero frequency to zero frequency to microwave frequencies,IEEE Transactions on Antennas and Propagation,Oct.2000,Vol.48,No.10,pp.1635-1645.
[14]Z.G.Qian and W.C.Chew,An augmented electric field integral equation for low frequency electromagnetcs analysis,IEEE Antennas and Propagation International Symposium,San Diego,Jul.2008.
[15]Z.G.Qian and W.C.Chew,An augmented EFIE for high speed interconnect analysis,Microwave and Optica Technology Letters,Oct.2008,Vol.50,No.10,pp.2658-2662.
[16]M.Taskinen and P.Yla-Oijala,Current and charg integral equation formulation,IEEE Transactions on Antennas and Propagation,Jan.2006,Vol.54,No.1,pp.58-67.
[2]逯贵祯,王宝发.高斯随机粗糙表面的电磁散射研究[J].电子学报,2002,30(6):907-908.
[3]Thorsos E.The validity of the Kirchhoff approximation for rough surface scattering using a Gaussian roughness spectrum[J].1/++7 J Acoust Soc Am,1988,83(1):78-91.
[4]Wang X,Wang C F,Gan Y B.Electromagnetic scattering from a circular target above or below rough surface[J].Progress in Electromagnetics Research,2003,40:207-227.
[5]Kuga Y,Phu P.Experimental studies of millimeterwave scattering in discrete random media and from rough surfaces[J].Progress in Electromagnetics Research,1996,14:37-38.
[6]闫沛文,童创明,姬伟杰.SM FSIA/CA G快速计算二维分形粗糙面的电磁散射特性[J].系统工程与电子技术,2009,31(9):2117-2120.
[7]田炜,任新成.一维指数型粗糙土壤表面电磁散射的矩量法研究[J].科学技术与工程,2011,11(10):2211-2214.
[8]郭立新,王蕊,吴振森.随机粗糙面散射的基本理论与方法[M].北京:科学出版社,2009:1-60.
[9]Bass.Wave Scattering from Statistically Rough Surfaces[C].Oxford:Pergamum,1979.
[10]A.Ishimaru,and J S.Chen.Scattering from very rough surfaces based on the modified second-order Kirchhoff approximation with angular and propagation shadowing[M].J.Acoust.Soc.Am,1990:1877-1883.
[11]Bruce N C.Multiple scatter of vector electromagnetic waves from rough metal surfaces with infinite slopes using the Kirchhoff approximation[J].Waves in Random and Complex Media,2011,21(2):362-377.
[12]W.Wu,A.W.Glisson and D.Kajfez.,A Comparison of Two Low-frequency Formulations for the Electric Field Integral Equation,Proceedings of the 10th Annual Review of Progress in Applied Computational Electromagnetics,Monterey,California,Vol.2,pp 484-491.
[13]J.S.Zhao,W.C.Chew,Integral equation solution of Maxwell's equations from zero frequency to zero frequency to microwave frequencies,IEEE Transactions on Antennas and Propagation,Oct.2000,Vol.48,No.10,pp.1635-1645.
[14]Z.G.Qian and W.C.Chew,An augmented electric field integral equation for low frequency electromagnetcs analysis,IEEE Antennas and Propagation International Symposium,San Diego,Jul.2008.
[15]Z.G.Qian and W.C.Chew,An augmented EFIE for high speed interconnect analysis,Microwave and Optica Technology Letters,Oct.2008,Vol.50,No.10,pp.2658-2662.
[16]M.Taskinen and P.Yla-Oijala,Current and charg integral equation formulation,IEEE Transactions on Antennas and Propagation,Jan.2006,Vol.54,No.1,pp.58-67.