Numerical errors in the computation of impedances by the FDTD method and ways to eliminate them

摘要

This paper presents numerical errors in the computation of impedances by the FDTD method. As shown by examples in the paper, substantial numerical errors can be introduced due to the spatial and time offsets of voltages and currents calculated from corresponding field variables in FDTD computations. An impedance calculation formula that completely eliminates such errors is also presented.