Review of the Memory-Efficient Algorithms of the High-Order Difference Equations in the Finite-Difference Time-Domain Method

The paper reviews memory-efficient algorithms of the high-order difference equations in the finite-difference time-domain (FDTD) method. In addition, the FDTD pseudo-code is provided for all methods. Through comparing the number of auxiliary variables and the implementation of the different memory-efficient algorithms available in the literature, it can be concluded that the algorithm proposed in [8] and [9], which is referred to as the simplest and memory-minimized algorithm in this paper, is a preferred choice in terms of the memory requirement and the implementation. A numerical example is included to demonstrate the effectiveness of these methods.