Flexible Design of Broadside-Radiating Linearly-Polarized Edge-Fed Metasurface Antennas

In this work, we design and fabricate broadside-radiating edge-fed metasurface antennas with linear polarization employing a spatially-varying isotropic reactance; in order to avoid losses, the antenna is not terminated on a matched load. The design is achieved using a deterministic numerical algorithm for the synthesis of metasurfaces, combined with an accurate modeling of the feeding structure. The procedure effectively keeps into account the open-ended layout of the antennas; remarkably, optimization of radiation, and input impedance matching, results in structures that are of standing-wave type or traveling (leaky)-wave type depending on the substrate. In case of leaky-wave type of result, it is shown that the related open stop-band issue is avoided. The performance of the designed antennas is tested by full-wave simulations and measurements of fabricated prototypes.