Discrete Green's function approach to disjoint domain simulations in 3D FDTD method.

A discrete Green's function (DGF) approach to couple 3D FDTD subdomains is developed. The total‐field/scattered‐field subdomains are simulated using the explicit FDTD method whilst interaction between them is computed as a convolution of the DGF with equivalent current sources measured over Huygens surfaces. In the developed method, the DGF waveforms are truncated using the Hann's window. The error varies in the range − 65 to − 40 dB depending on the DGF length and positions of the subdomains. However, if the DGF length is equal to the number of iterations in a simulation, this approach returns the same results as the direct FDTD method. [ABSTRACT FROM AUTHOR]