Efficient Leapfrog LOD-FDTD Method for Periodic Structures at Oblique Incidence

To solve the issues of obliquely incident plane wave on periodic structures, an efficient Leapfrog locally one-dimensional (LOD) FDTD method was proposed in this paper. Firstly, by applying the LOD scheme into the improved split-field algorithm, unconditional stability can be achieved. And then, by introducing three auxiliary variables, the one-step Leapfrog implementation for the LOD scheme was derived. Compared with the traditional periodic LOD-FDTD algorithm [5], the proposed method is more efficient and needs the less stored memory. At last, numerical results were given to verify the accuracy and effectiveness of the proposed method.