Two-dimensional Quasi-Bessel Beam Synthesis and Frequency-scanning Leaky-wave Launchers

In this paper, a technique to synthesize a 2D frequency-scanned high order Bessel beam in a parallel plates waveguide (PPW) scenario is presented. This technique is based on a one dimensional beam launcher, rather than the more typical axicons or the more recent metasurfaces and antenna arrays for 3D Bessel beam synthesis. With this launcher, it is possible to generate a 2D Bessel beams whose direction can be controlled by changing the frequency of the feeding signal in the Ku band from 14.5 GHz to 15 GHz. It is demonstrated how this can be done by combination of two leaky waves (LW), which can be created by the same 1D structure, scanning at different angles and launched to the PPW region. The beams are generated in a triangular area, with one of its sides being the launcher itself and the other sides are defined by the direction of radiation of each of the forming leaky waves.