中国物理B ›› 2019, Vol. 28 ›› Issue (7): 74102-074102.doi: 10.1088/1674-1056/28/7/074102

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

New hybrid FDTD algorithm for electromagnetic problem analysis

Xin-Bo He(何欣波), Bing Wei(魏兵), Kai-Hang Fan(范凯航), Yi-Wen Li(李益文), Xiao-Long Wei(魏小龙)   

  1. 1 School of Physics and Optoelectronic Engineering, Xidian University, Xi'an 710071, China;
    2 Collaborative Innovation Center of Information Sensing and Understanding at Xidian University, Xi'an 710071, China;
    3 Science and Technology on Plasma Dynamic Laboratory, Airforce Engineering University, Xi'an 710038, China
  • 收稿日期:2019-03-08 修回日期:2019-05-13 出版日期:2019-07-05 发布日期:2019-07-05
  • 通讯作者: Bing Wei E-mail:bwei@xidian.edu.cn
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant No. 61571348) and the Equipment Pre-Research Foundation of China (Grant No. 61405180202).

New hybrid FDTD algorithm for electromagnetic problem analysis

Xin-Bo He(何欣波)1,2, Bing Wei(魏兵)1,2, Kai-Hang Fan(范凯航)1,2, Yi-Wen Li(李益文)3, Xiao-Long Wei(魏小龙)3   

  1. 1 School of Physics and Optoelectronic Engineering, Xidian University, Xi'an 710071, China;
    2 Collaborative Innovation Center of Information Sensing and Understanding at Xidian University, Xi'an 710071, China;
    3 Science and Technology on Plasma Dynamic Laboratory, Airforce Engineering University, Xi'an 710038, China
  • Received:2019-03-08 Revised:2019-05-13 Online:2019-07-05 Published:2019-07-05
  • Contact: Bing Wei E-mail:bwei@xidian.edu.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant No. 61571348) and the Equipment Pre-Research Foundation of China (Grant No. 61405180202).

摘要:

Since the time step of the traditional finite-difference time-domain (FDTD) method is limited by the small grid size, it is inefficient when dealing with the electromagnetic problems of multi-scale structures. Therefore, the explicit and unconditionally stable FDTD (US-FDTD) approach has been developed to break through the limitation of Courant-Friedrich-Levy (CFL) condition. However, the eigenvalues and eigenvectors of the system matrix must be calculated before the time iteration in the explicit US-FDTD. Moreover, the eigenvalue decomposition is also time consuming, especially for complex electromagnetic problems in practical application. In addition, compared with the traditional FDTD method, the explicit US-FDTD method is more difficult to introduce the absorbing boundary and plane wave. To solve the drawbacks of the traditional FDTD and the explicit US-FDTD, a new hybrid FDTD algorithm is proposed in this paper. This combines the explicit US-FDTD with the traditional FDTD, which not only overcomes the limitation of CFL condition but also reduces the system matrix dimension, and introduces the plane wave and the perfectly matched layer (PML) absorption boundary conveniently. With the hybrid algorithm, the calculation of the eigenvalues is only required in the fine mesh region and adjacent coarse mesh region. Therefore, the calculation efficiency is greatly enhanced. Furthermore, the plane wave and the absorption boundary introduction of the traditional FDTD method can be directly utilized. Numerical results demonstrate the effectiveness, accuracy, stability, and convenience of this hybrid algorithm.

关键词: unconditionally stable, hybrid FDTD algorithm, electromagnetic problem

Abstract:

Since the time step of the traditional finite-difference time-domain (FDTD) method is limited by the small grid size, it is inefficient when dealing with the electromagnetic problems of multi-scale structures. Therefore, the explicit and unconditionally stable FDTD (US-FDTD) approach has been developed to break through the limitation of Courant-Friedrich-Levy (CFL) condition. However, the eigenvalues and eigenvectors of the system matrix must be calculated before the time iteration in the explicit US-FDTD. Moreover, the eigenvalue decomposition is also time consuming, especially for complex electromagnetic problems in practical application. In addition, compared with the traditional FDTD method, the explicit US-FDTD method is more difficult to introduce the absorbing boundary and plane wave. To solve the drawbacks of the traditional FDTD and the explicit US-FDTD, a new hybrid FDTD algorithm is proposed in this paper. This combines the explicit US-FDTD with the traditional FDTD, which not only overcomes the limitation of CFL condition but also reduces the system matrix dimension, and introduces the plane wave and the perfectly matched layer (PML) absorption boundary conveniently. With the hybrid algorithm, the calculation of the eigenvalues is only required in the fine mesh region and adjacent coarse mesh region. Therefore, the calculation efficiency is greatly enhanced. Furthermore, the plane wave and the absorption boundary introduction of the traditional FDTD method can be directly utilized. Numerical results demonstrate the effectiveness, accuracy, stability, and convenience of this hybrid algorithm.

Key words: unconditionally stable, hybrid FDTD algorithm, electromagnetic problem

中图分类号:  (Electromagnetic wave propagation; radiowave propagation)

  • 41.20.Jb
02.70.Bf (Finite-difference methods) 02.60.Cb (Numerical simulation; solution of equations)