Enhanced Bandwidth Fabry-Pérot Cavity Antenna Synthesis with Controlled Aperture Distribution and Practical Excitation

This paper presents a systematic approach to broadband Fabry-Pérot Cavity Antenna (FPCA) synthesis, integrating ray-optics and leaky-wave perspectives to overcome limitations of traditional heuristic designs. By precisely engineering the Partially Reflective Surface (PRS) properties, desired radial aperture field distributions are achieved, enabling radiation pattern shaping and enhancing aperture efficiency. Simultaneously, a positive-slope phase technique is employed to increase the operational bandwidth. Furthermore, the practical excitation of FPCAs is addressed, considering fundamental feeding limitations and offering guidelines for the primary source selection. The methodology is validated through three different FPCA designs that use single both-side-etched laminate PRSs. The experimental results of the fabricated prototypes are compared to full-wave simulations, demonstrating improved directivity-bandwidth product and successful excitation using a printed dipole feed.