Systematic Design of THz Leaky-Wave Antennas based on Homogenized Metasurfaces

In this work, a systematic design of Fabry-Perot cavity antennas based on leaky waves is proposed in the THz range. The use of different topologies for the synthesis of homogenized metasurfaces shows that a specific fishnet-like unit-cell is particularly suitable for the design of efficient THz radiating devices. Accurate full-wave simulations highlight advantages and disadvantages of the proposed geometries, thoroughly considering the bounds dictated by technological constraints and the homogenization limit as well. The radiative performance of different designs for achieving theoretical directivities ranging from 15 dB to 30 dB is evaluated with reliable analytical and numerical methods, and completely validated with full-wave simulations. The relevant results corroborate the proposed systematic design, consolidating the validity and the usefulness of the leaky-wave approach, well-established at microwave frequencies, to the more challenging and still unexplored THz range.