Ricerc@Sapienza

The history of leaky waves and leaky-wave antennas is an interesting one, with much of the theory being put on a firm foundation in the 1950s and 1960s by early pioneers such as Nathan Marcuvitz and Arthur A. Oliner. Rapid development of leaky-wave antennas took place after the foundation was established, and the development spread to areas such as printed-circuit technology, optics, and metamaterials. This presentation will review some of the basic history of leaky waves and leaky-wave antennas, and discuss some of the recent advances in the field.

We describe the possibility of achieving enhanced radiation performance introducing multiple sources within a two-dimensional structure supporting one or more cylindrical leaky-waves. The device is planar and made by a grounded dielectric slab loaded on top by a periodic arrangement of metallic strips or patches and it is fed by an array of simple, fully integrated, dipoles.

Bessel-Gauss beams have mainly been proposed in optics as a solution for reducing the on-axis intensity oscillations typical of Bessel beams. Previous investigations on Bessel-Gauss beams are based on a scalar theory in the paraxial approximation, and thus cannot be extended to the microwave range where a fully vectorial approach is needed. Here, the generation of Bessel-Gauss beams through leaky waves is investigated. First, the nondiffractive and focusing properties of Bessel-Gauss beams generated through leaky waves are extensively examined in the frame of a vectorial approach.

Ahstract - A novel millimeter-wave design of a Fabry-Perot cavity leaky-wave antenna (LWA) is proposed here as a promising alternative to conventional configurations for improving the directivity at broadside of radiating elements.