Quantifying Sub-gridding Errors in Standard and Hybrid Higher Order 2D FDTD Simulations


  • Madison Le Electrical Engineering Department Colorado School of Mines Golden, USA
  • Mohammed Hadi Electrical Engineering Department Colorado School of Mines Golden, USA
  • Atef Elsherbeni Electrical Engineering Department Colorado School of Mines Golden, USA


Finite-difference time-domain method, high order FDTD, numerical error analysis, sub-gridding


Sub-gridding errors for a 2D Finite-Difference Time-Domain (FDTD) simulation are compared for both the standard FDTD and Hybrid higher order FDTD cases. Subgridding contrast ratios of 1:3, 1:9, 1:15, and 1:27 are considered and analyzed. A correlation is seen between the increase of contrast ratio with the increase of sub-gridding errors for both standard and hybrid cases. However, a trend of errors reduction when using hybrid formulations over standard formulations is apparent for each contrast ratio.


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