Ray Optics Analysis Explanation of Beam-Splitting Condition in Fabry-Pérot Antennas

This paper presents a theoretical analysis where general and accurate formulas for the design of Fabry-Pérot antennas (FPA) are derived from a simple ray optics approach. The beam-splitting condition predicted from the leaky-wave (LW) theory is analyzed here from ray optics analysis. Excellent agreement is observed with the results obtained from the LW analysis in a significant frequency range. Thereby, these expressions allow to design FPAs accurately without performing dispersion analysis of the leaky modes inside the structure.