Introducing the equivalence source in 2D-FDTD method to improve the computational speed

The equivalence source finite-difference time-domain method is proposed to improve the computational speed without increasing extra computation resource. The proposed method introduces some equivalent electromagnetic current on a virtual closed surface surrounded by the real radiated source. By building up exchanged formulas between the real source and the equivalence source, we can expand the computation time step and reduce the computation time. Demonstrated by numerical results, the equivalence source finite-difference time-domain method is in good agreement with the conventional finite-difference time-domain method.