Ricerc@Sapienza

A novel terahertz (THz) Fabry–Perot cavity (FPC) antenna is proposed, based on a multistack of alternating layers of highly birefringent nematic liquid crystal (NLC) and highpermittivity dielectric, which comprehensively acts as a Bragg reflector. This layout is able to provide enhanced reconfigurability

A technique for the open-stopband (OSB) suppression in one-dimensional (1-D) periodic leaky-wave antennas based on a double asymmetric series/shunt discontinuity inside the unit cell is discussed and applied to a canonical 2-D structure. A longitudinal equivalent network formalism is developed here to analyze the unit-cell matching, which confirms that the OSB suppression cannot be achieved using a double symmetric discontinuity.

In this work, the spatially dispersive behavior of three different metasurface geometries has been investigated. A patch-like, a strip-like, and a fishnet-like unit cell have been compared in terms of their surface impedance for different angle of incidence at terahertz frequencies. The fishnet-like metasurface shows a TE-TM polarization independent behavior and a remarkable non-dispersive behavior, opening to very interesting possibilities in the design of Fabry-Perot cavity leaky-wave antennas with a reconfigurable pointing angle and equalized patterns at terahertz frequencies.

In this paper, 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 fishnetlike unit cell is particularly suitable for the design of efficient THz radiating devices. Accurate full-wave simulations highlight the advantages and disadvantages of the proposed geometries, thoroughly considering the bounds dictated by technological constraints and the homogenization limit as well.