An efficient splitting the plane-wave FDTD method

The paper presents a new efficient method of introduction of plane wave source into finite difference time domain (FDTD) grids: the method of splitting the plane-wave FDTD (SP-FDTD). The new equations for the 1-D propagator are based on spitted-field Maxwell´s equations, and the propagator makes the 1-D and 2-D dispersion equations identical. The technique virtually eliminates numerical dispersion, filed location and polarization mismatches between propagator and main grid, for a plane wave propagating at an angle forming an integer grid cell ratio, which can represent almost any angle in theory. Through the leak test of the different incident angles of the Gauss pulse plane wave source in 2-D, it shows that, the technique can achieve a perfect total-field scattered-field separation, making leakage down to -340 dB levels.