True Time Delay Multiple Beam Antenna System Design Tool

Accurate analysis of multiple wavelength structures which contain regions with fine details is a challenging problem. A full wave method such as the Finite Difference Time Domain (FDTD) method can be used to analyze large structures as long as enough computer memory is available. High frequency ray methods based on the Uniform Theory of Diffraction (UTD) are often used for cases where the structure is very large in terms of wavelengths and the desired output can be determined from the interaction of rays bounced off the structure. In some instances, neither approach is sufficient by itself but the two are combined to analyze a large, complex structure. In the case of a Rotman Lens, a staged approach may be used with a high frequency method applied to the basic lens design and optimization and a full-wave FDTD solution used for more accurate results. To be practical the tool must incorporate CAD design with suitable output for fabricating the actual components. The development of this hybrid solver with optimization and CAD input/output capabilities will be the main focus of the proposed effort.