Adjoint sensitivity analysis of 3D problems with anisotropic materials

A novel time-domain adjoint variable method (AVM) algorithm for general 3D anisotropic and inhomogeneous materials based on the transmission line modeling (TLM) is proposed. The developed algorithm enables sensitivity analysis of an arbitrary lossless anisotropic material with possibly non diagonal material tensors. The anisotropic material property can be the permittivity, permeability, conductivity as well as the coupling between the electric and magnetic fields. The theory has been applied to the sensitivity calculation of computationally intensive three dimensional (3D) structures. Our results match well the expensive conventional finite difference approaches.