Efficient Finite-Difference Time-Domain (FDTD) Modeling of Periodic Leaky-Wave Structures

This paper reports the application of a Finite Difference Time Domain (FDTD) technique for the determination of the complex propagation constants in periodic leaky-wave structures. In the past, these calculations would be typically performed through the brute-force simulation of a finite number of unit cells. In this work, the well-known sine-cosine method is combined with a numerical procedure, established in the FDTD analysis of lossy structures, for the fast and complete numerical characterization (determination of leakage and dispersion) of a periodic leaky-wave structure, using a single unit cell.