Analysis and Design of Sub-Wavelength Resonant Cavity Type 2-D Leaky-Wave Antennas

A rigorous analysis is presented together with novel designs of high-gain sub-wavelength resonant cavity antennas. The antennas under investigation are formed by partially reflective surfaces placed in close proximity over artificial periodic metamaterial ground planes with specific reflection phase responses. A full-wave periodic leaky-wave analysis is applied to this class of antennas for the first time and the results are reported and discussed. Finite-size antenna designs are studied at wireless LAN frequencies (3.7 GHz) using 3-D full-wave software and the results are compared to the predictions of the leaky-wave analysis. Furthermore, the field distribution and the effect of losses are investigated. Finally, practical designs of sub-wavelength 2-D leaky-wave antennas with high-gain performance are presented.