Abstract

Quasiconformal Transformation Optics (QCTO) has been investigated and applied for the design of innovative electromagnetic field manipulating devises. The design is focused on enhancing radiation performance of antenna arrays. Towards this end, the QCTO approach has been utilized for the application of compressing dimension of linear array at the same time keeping its radiation performance equivalent to the original array. The basic QCTO is then generalized to allow an arbitrary physical arrangement coated with a suitable lens to exhibit the same radiating features of an arbitrary reference virtual array in free space. This removed the limitation on the state-of-the-art QCTO method to handle transformation between arbitrarily shaped geometries. A representative numerical example, concerned with a two-dimensional layout, is presented to assess the effectiveness of the proposed method as well as the enhanced features of the resulting metamaterial-coated arrays with respect to standard conformal arrangements. In addition, the capability to achieve significantly simplified structures by means of tile discretization approximation of the synthesized lens is investigated. Selected numerical examples are reported to illustrate the effectiveness of tile-discretized lenses versus ideal QCTO arrangements. The metamaterial lens that resulted from the extended QCTO was found to be significantly anisotropic posing implementation challenge. To address this issue, an innovative approach, based on the System-by-Design (SbD) paradigm, is proposed for the synthesis of isotropic non-magnetic metamaterial lenses. Selected numerical results, concerned with an application of the SbD-QCTO approach, are reported to give some insights on its advantages and current limitations in terms of computational efficiency, effectiveness, and flexibility.