Experimental validation of Bessel beam generation using an inward Hankel aperture distribution

Mauro Ettorre (1) , Santi Concetto Pavone (2) , Massimiliano Casaletti (3) , Matteo Albani (2)

1 IETR - Institut d'Électronique et des Technologies du numéRique
2 DII - Department of Information Engineering [Sienne]
3 L2E - Laboratoire d'Electronique et Electromagnétisme

In this paper we prove experimentally that nondiffractive Bessel beams can be generated by using inward cylindrical traveling wave aperture distributions. An azimuthally invariant inward traveling wave distribution is defined over the aperture of a Radial Line Slot Array (RLSA) to launch a Bessel beam whose normal electric-field component assumes a truncated, zeroth-order Bessel function. An optimization procedure based on a holographic approach is used for tuning the position and size of the slots of the RLSA. The antenna is centrally fed by a coaxial probe transition. The final structure operates at 12.5 GHz. Full-wave simulations and measurements of the vertical component of the electric field show that a non-diffractive radiation is obtained within a range larger than 12 wavelengths in front of the antenna. The generated Bessel beam presents a stable half power beamwidth of about 20 mm within this range. The proposed system may open new opportunities for planar, low profile Bessel beam generators at millimeter waves, Terahertz, and optics.

Mots clés: radial line slot array; Bessel beams; RLSA; focusing; near field

Domaines: Electromagnétisme

Mauro Ettorre, Santi Concetto Pavone, Massimiliano Casaletti, Matteo Albani. Experimental validation of Bessel beam generation using an inward Hankel aperture distribution. IEEE Transactions on Antennas and Propagation, 2015, 63 (6), pp.2539-2544. ⟨10.1109/TAP.2015.2419261⟩. ⟨hal-01154649⟩