A three-dimensional FDTD subgridding algorithm with separated temporal and spatial interfaces and related stability analysis

Kai Xiao*, David J. Pommerenke, James L. Drewniak

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


A finite-different time-domain subgrid algorithm locally refines the mesh at regions requiring higher resolution. A novel separation of spatial and temporal subgridding interfaces is presented that allows implementing a novel spatial subgridding method and investigating the stability of each subalgorithm individually. Details are given for a spatial subgridding algorithm having a 1:3 mesh ratio. In the spatial subgridding algorithm, the fine-mesh is constructed with a recessed interface and the interpolation scheme is designed to be symmetric to maintain the stability of the update process. The stability of the spatial subgridding algorithm is analyzed with a matrix method. Numerical examples showing stability and accuracy are provided.

Original languageEnglish
Pages (from-to)1981-1990
Number of pages10
JournalIEEE Transactions on Antennas and Propagation
Issue number7
Publication statusPublished - 1 Jul 2007
Externally publishedYes


  • Finite-difference time-domain (FDTD)
  • Stability
  • Subgrid

ASJC Scopus subject areas

  • Electrical and Electronic Engineering

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