Validation of Integral Equation Model with High-Dielectric Microstrip Rotman Lens Measurements,

Abstract : To reduce the physical size of a Rotman lens, a reduction in the overall electrical size of the lens can be combined with a microstrip fabrication using substrate materials with large relative permittivities such as TiO2. An integral equation formulation for predicting the scattering matrix (S-matrix) associated with a Rotman lens has been developed to aid in the design of a compact, low-sidelobe, high-performance lens. The model incorporates the tapered transitions used to transform from 50 Omega transmission lines to the larger lens apertures, and in principle is limited only by the assumption that the device behaves as a planar circuit. S-parameter measurements obtained from a lens having dielectric constant of 100 will be compared with theoretical predictions in order to validate this model.