A NOVEL NONUNIFORM SUBGRIDDING SCHEME FOR FDTD USING AN OPTIMAL INTERPOLATION TECHNIQUE

Finite-Difierence Time-Domain (FDTD) subgridding schemes can signiflcantly improve e-ciency of various electromagnetic circuit simulations. However, numerous subgridding schemes sufier from issues associated with stability, e-ciency, and material traverse capability. These issues limit general applicability of FDTD subgrid- ding schemes to realistic problems. Herein, a robust nonuniform sub- gridding scheme is presented that overcomes those weaknesses. The scheme improves simulation accuracy with the aid of greatly increased stability margin and an optimal interpolation technique. It also im- proves simulation e-ciency by allowing the use of time step factors as close as the Courant-Friedrichs-Lewy (CFL) limit. In addition, late- time stability and general applicability are verifled through practical microstrip circuit simulation examples.

[1]  R. Lee,et al.  Conservative and Provably Stable FDTD Subgridding , 2007, IEEE Transactions on Antennas and Propagation.

[2]  M.H. Kermani,et al.  The complementary derivatives method: a second-order accurate interpolation scheme for non-uniform grid in FDTD simulation , 2006, IEEE Microwave and Wireless Components Letters.

[3]  M. Okoniewski,et al.  Three-dimensional subgridding algorithm for FDTD , 1997 .

[4]  C. J. Railton,et al.  A stable subgridding algorithm and its application to eigenvalue problems , 1999 .

[5]  Cleve B. Moler,et al.  Numerical computing with MATLAB , 2004 .

[6]  R.J. Luebbers,et al.  FDTD local grid with material traverse , 1996, IEEE Antennas and Propagation Society International Symposium. 1996 Digest.

[7]  M. Mrozowski,et al.  Low-reflection subgridding , 2005, IEEE Transactions on Microwave Theory and Techniques.

[8]  C.D. Sarris,et al.  Efficient modeling of microwave integrated-circuit geometries via a dynamically adaptive mesh Refinement-FDTD technique , 2006, IEEE Transactions on Microwave Theory and Techniques.

[9]  J. Bérenger.  A Huygens Subgridding for the FDTD Method , 2006, IEEE Transactions on Antennas and Propagation.

[10]  M. F. Iskander,et al.  A new 3D FDTD multigrid technique with dielectric traverse capabilities , 2001 .

[11]  F. Teixeira,et al.  Improved FDTD subgridding algorithms via digital filtering and domain overriding , 2005, IEEE Transactions on Antennas and Propagation.

[12]  Thomas Weiland,et al.  A CONSISTENT SUBGRIDDING SCHEME FOR THE FINITE DIFFERENCE TIME DOMAIN METHOD , 1996 .

[13]  D. M. Sheen,et al.  Application of the three-dimensional finite-difference time-domain method to the analysis of planar microstrip circuits , 1990 .

[14]  L. Cristoforetti,et al.  A robust and efficient subgridding algorithm for finite-difference time-domain simulations of Maxwell's equations , 2004 .