Compact Multifunctional Gain Enhancing GRIN Lens for Widely Separated Frequency Band Shared Aperture Antennas

摘要

Gradient index (GRIN) lenses embody a powerful technology that enablescontrol of electromagnetic wave propagation over wide frequency bands.However, GRIN lenses that achieve multifunctional (i.e., dual broadband) performancehave not been realized mainly due to the limitations of conventionaltechniques such as Transformation Optics (TO). This paper proposes a multiobjectiveinverse-design approach for the optimization of multi-band GRINlenses with highly constrained aperture sizes. A candidate lens design is fabricatedfrom a ceramic material using a new additive manufacturing approachallowing for spatially-varying permittivities between 2–6.5 to be achieved atsub-cm resolution. Measured results validate the candidate functionalizedceramic GRIN lens's simulated multi-band performance and demonstrate theefficacy of the proposed inverse-design procedure.