| The Finite-Difference Time-Domain (FDTD) method has gained tremendous popularity in the past decade as a tool for solving Maxwell's equations. Phased Array Antennas find several applications including mobile communications (cellular, personal communication systems and networks), satellite communications, global positioning system (GPS), aeronautical and radar systems. This dissertation describes the application of the FDTD method for calculating broadband characteristics of finite-sized phased array antennas consisting of microstrip elements fed with coaxial probes.; The characterization of such antennas is dependent upon the development of simulation tools that can accurately model general topologies including wires, dielectrics, conductors, lumped elements and metallic strips. The use of these simulation tools reduces the cost and effort associated with fabricating and testing phased array antennas. The FDTD formulation is inherently broadband, very general, and easily accommodates arbitrary conductor geometry and dielectric configurations.; The FDTD method is implemented and applied to determine the input impedance, radiation-patterns and gain of microstrip antennas. Next, the main contributions of this work are described which include the full time-domain characterization of broadband characteristics of finite-sized phased array antennas for different scan conditions. Active reflection coefficient, gain, scan-element patterns and scanning-array radiation patterns are calculated. |
