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arXiv · 1902.03956

Efficient Computation of High-Order Electromagnetic Field Derivatives for Multiple Design Parameters in FDTD

Kae-An Liu·Costas D. Sarris
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Abstract

This paper introduces a new computational framework to derive electromagnetic field derivatives with respect to multiple design parameters up to any order with the Finite-Difference Time-Domain (FDTD) technique. Specifically, only one FDTD simulation is needed to compute the first-order field derivatives with respect to N parameters, while two FDTD simulations are needed to compute the field derivatives with respect to one parameter up to any order. The field derivatives with respect to N parameters up to any order are computed with (N+1) FDTD runs. In addition to its efficiency, this framework is based on a subtractive cancellation error-free approach, providing guaranteed accuracy toward the computation of field derivatives up to any order. With high-order field derivatives available, sensitivity analysis, parametric modelling and uncertainty quantification can be accurately performed.

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Kae-An Liu, Costas D. Sarris. 2019-02-11. Efficient Computation of High-Order Electromagnetic Field Derivatives for Multiple Design Parameters in FDTD. https://doi.org/10.1109/tmtt.2019.2929046

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