Exciting Vorticity Through Higher Order Bessel Beams With a Radial-Line Slot-Array Antenna

Abstract

International audienceIn this communication, it is shown that a nondiffracting vortex beam (i.e., a higher order Bessel beam with azimuthal phase variation) can be generated in the near field by synthesizing an inward cylindrical traveling-wave distribution over a finite aperture antenna. A radial line slot array (RLSA) is then designed to prove the concept. The collimated vortex beam is excited in the proximity of the RLSA, within a region properly defined by the nondiffracting range of the generated beam. The radial dependence of the longitudinal electric field of the vortex-beam magnitude follows a first-order Bessel function, and its phase presents a linear azimuthal variation. Full-wave results validate the generation of the nondiffractive higher order Bessel beam within the radiative near field of the launcher

Generation of Bessel beams with 3D‐printed lens

“…[2][3][4] In optical domain, Bessel beam is generated by using the spatial light modulator, the circular slit, the axicon, and the hologram. [5][6][7][8] The spatial light modulator system is complex to realize. The circular slit and the axicon are very simple.…”

Characterization of an Eight-Element Circular Patch Array for Helical Beam Modes

“…ELICAL beams (HB) and the associated beam property referred to as Orbital Angular Momentum (OAM) [1] have generated considerable interest [2] in recent years and in consequence a wide diversity of proposals for so-called OAM antennas has appeared in the engineering and science literature, mostly over the last decade [3][4][5][6][7][8][9][10][11][12]. It has been mathematically demonstrated that communication range using a pair of transmit-receive OAM antennas will be limited, for example in [13] where link transmittance was derived as a function of distance and helical mode index.…”

A new class of nondiffracting pulses based on focusing leaky waves

“…Nevertheless, it has recently been shown that Bessel beams can conveniently be generated using inward cylindrical waves only [15][16][17], thus leading to the design of wideband radiators. (Note that in [15] analytical results are obtained for zeroth-order Bessel beams, whereas in [17] numerical results are extended to higher orders.) Even more interestingly, in [18] this principle has been successfully used to design a sinusoidally-modulated LWA based on the excitation of a backward leaky wave.…”