Connective boundary's electromagnetic leakage in finite-difference time-domain
-
摘要: 用时域有限差分法计算目标的雷达散射截面时,一般用连接边界来引入平面入射波.理想情况下,当总场区没有散射目标时,该区域仅有入射波,散射场区电磁波为0.但在实际计算过程中,散射场区的电磁波一般不会严格等于0,这是因为在连接边界引入入射波时产生了电磁泄漏.一维情形下,用散射场区电场的平方和来衡量电磁泄漏程度.二维情形下,用等效原理将散射场区的电磁场进行远场外推,得到雷达散射截面,以此衡量电磁泄漏的大小.研究表明:时间步长、入射角度都能影响电磁泄漏大小.为使电磁泄漏较小,时间步长应接近于稳定性要求的最小步长,入射方向应避免垂直于计算区域边界.Abstract: When calculating target's radar cross section(RCS) with finite-difference time-domain(FDTD), the incident wave was induced using connective boundary. In ideal situation without scattering target, there is only incident wave in total field region and the field in scattering field region is zero. But in practical calculating process, the electromagnetic wave in scattering field region is not rigidly zero because of leakage in connective boundary. In 1-dimensional situation, the leakage was measured by sum of squared electric field. In 2-dimensional situation, the leakage was measured by RCS which acquired by far field transformation of electromagnetic field in scattering field region using equivalent principle. Research results show that time step and incident angle influence the leakage very much. The leakage is small when the time step is near the least step needed for the stable requirement and the incident direction avoids impinging the connection boundary perpendicularly.
-
[1] 郑奎松,葛德彪,魏兵.导弹目标的FDTD建模与RCS计算[J].系统工程与电子技术,2004,26(7):896-899 Zheng Kuisong,Ge Debiao,Wei Bing.FDTD modeling of missile target and RCS computation[J].Systems Engineering and Electronics,2004,26(7):896-899(in Chinese) [2] 李军,武振波,武哲.稳定因子对FDTD 数值计算的影响[J].北京航空航天大学学报,2004,30(1):70-73 Li Jun,Wu Zhenbo,Wu Zhe.Effects of stability factor on FDTD numerical calculation[J].Journal of Beijing University of Aeronautics and Astronautics,2004,30(1):70-73(in Chinese) [3] 黄志祥,沙威,吴先良,等.辛FDTD 算法[J].系统工程与电子技术,2009,31(2):456-458 Huang Zhixiang,Sha Wei,Wu Xianliang,et al.Scheme of symplectic FDTD[J].Systems Engineering and Electronics,2009,31(2):456-458(in Chinese) [4] 胡晓娟,卢兆林,葛德彪,等.基于三角面元的涂层目标FDTD 共形网格生成技术[J].系统工程与电子技术,2010,32(9):1884-1888 Hu Xiaojuan,Lu Zhaolin,Ge Debiao,et al.Conformal FDTD mesh-generating scheme for coated targets based on triangle-patch[J].Systems Engineering and Electronics,2010,32(9):1884-1888(in Chinese) [5] 葛德彪,闫玉波.电磁波时域有限差分方法[M].2版.西安:西安电子科技大学出版社,2005 Ge Debiao,Yan Yubo.Finite-difference time-domain method for electromagnetic waves[M].2nd ed.Xi-an:Xidian University Press,2005(in Chinese) [6] 王长清.现代计算电磁学基础[M].北京:北京大学出版社,2004 Wang Changqing.Basic of modern computational electromagnetics[M].Beijing:Peking University Press,2004(in Chinese) [7] 姜彦南,葛德彪,魏兵.时域有限差分并行算法中的吸收边界研究[J].系统工程与电子技术,2008,30(9):1636-1640 Jiang Yannan,Ge Debiao,Wei Bing.Study on absorbing boundary condition in parallel FDTD algorithm[J].Systems Engineering and Electronics,2008,30(9):1636-1640(in Chinese) [8] Wang Hui,Huang Zhixiang,Wu Xianliang,et al.Perfect plane wave injection into 3D FDTD (2,4) scheme[C]//Cross Strait Quad-Regional Radio Science and Wireless Technology Conference (CSQRWC)Volume 1.Harbin:IEEE,2011:40-43 [9] Hadi M F.A versatile split-field 1-D propagator for perfect FDTD plane wave injection[J].IEEE Transactions on Antennas and Propagation,2009,57(9):2691-2697 [10] Huang Z,Pan G,Pan H K.Perfect plane wave injection for Crank-Nicholson time-domain method[J].Microwaves,Antennas & Propagation,IET,2010,4(11):1855-1862
点击查看大图
计量
- 文章访问数: 1566
- HTML全文浏览量: 162
- PDF下载量: 3488
- 被引次数: 0