Efficient Sensitivity Analysis of Microwave Structures with Multiple Design Parameters in FDTD

摘要

Exploiting the structure of the Finite-Difference Time-Domain (FDTD) update equations, a direct method to compute electromagnetic field derivatives with respect to multiple design parameters is derived. This method is based on recursively computing field derivatives up to any order$n$, by simulating the original unperturbed FDTD grid, excited by equivalent sources that depend on field derivatives of order zero to$n-1$. Derivatives with respect to any other field-based function of interest (such as scattering parameters or multiphysics quantities) can be easily comnuted, over the whole bandwidth of an FDTD simulation.