Steady-state response by time-reversal FD-TD method with Lanczos algorithm

Finite-difference time-domain (FD-TD) method combined with Lanczos algorithm and time-reversal technique is proposed for the steady-state response. With Lanczos algorithm, modes of FD-TD operator can be extracted efficiently. The steady-state response can then be calculated at any time by an analytic formula with a few of these modes. The existing FD-TD code needs not to be modified, except for an additionally time-reversal electric field update. An example of an air-filled cavity is demonstrated for the validation of this hybrid method.