Reineix and Jecko [179] were the first to apply the FDTD method to the analysis of microstrip antennas. In 1992, Leveque et al. [180] modeled frequency dispersive microstrip antennas while Wu et al. [181] used the FDTD method to accurately measure the reflection coefficient of various microstrip patch configurations. Uehara and Kagoshima [182] presented an analysis of the mutual coupling between two microstrip antennas while Oonishi et al. [183] and Kashiwa et al. [184] used one of the conformal FDTD approaches to analyze microstrip antennas on a curved surface. In 1994, Qian et al. [185] used the FDTD method to design twin-slot antennas. Recently, Reineix and co-workers [186,187,188] have expanded their FDTD analysis to include the input impedance of microstrips with slots, to obtain the radar cross section of microstrip patch antennas, and to model the radiation from microstrip patches with a ferrite substrate.