Wave Equation-Based Compact FDTD Algorithm for Longitudinally Magnetized Ferrite-Loaded Structures

In this paper, a compact finite-difference time-domain (FDTD) algorithm involving only the transverse components of the magnetic field and the magnetic induction is proposed for the dispersion analysis of longitudinally magnetized ferrite structures. Details of the implementation are presented as follows: 1) discretization; 2) boundary treatment; 3) the treatment of interfaces; and 4) the treatment of conductors. The constitutive relation of ferrite is simplified then suitably discretized using approximating formulas obtained from the Mobius transform technique. Some examples are presented to validate the algorithm with numerical results; good agreement is obtained by comparison with other frequency domain methods. A significant reduction in memory space requirements compared with other FDTD methods is also achieved.