Orbital angular momentum wave generation/detection based on planar multi‐slot‐spiral circularly polarized antenna

Abstract

Orbital angular momentum (OAM) as vortex wave has potential application for dense communication. A multislot antenna is proposed based on Archimedean spirals to generate/detect the OAM waves. The antenna equips three radiation slots in a disk-manner to realize three different OAM modes simultaneously. A serial-fed microstrip array is designed for circularly polarized (CP) radiation. The lengths of the slots and microstrip lines are chosen to radiate at 3.5 GHz with 20% fractional bandwidth. So, it can identify the receiving modes of vortex wave with this mechanism. A prominent spiral phase plane is observed for the generated OAM wave. In addition, the far-field pattern presents a doughnut-shape beam. The whole antenna is fabricated on a 13 cm printed circuit disk board. Both the experimental and simulation results show that the proposed antenna has valuable features to produce different vortex modes.

Optimized planar printed UCA configurations for OAM waves and the associated OAM mode content at the receiver

“…11,12 These methods of OAM mode synthesis have also been successfully applied in the mmWave frequency range. [13][14][15][16] Other proposed OAM mode synthesis methods for mmWave and microwave frequency ranges include ring-slot traveling-wave antennas, 17 plane spiral OAM (PSOAM) antennas, 18,19 planar multi-slot-spiral antennas, 20 patch antennas, 21,22 twisted parabolic antennas, 23 hemispherical dielectric resonator antenna, 24 reflectarray antennas, 25 metasurfaces, 26,27 metasurface-based antenna array, 28 and phased uniform circular antenna arrays (UCA). 4,[29][30][31][32][33][34][35][36] Ring-slot traveling-wave antennas are robust and offer the advantage of high modal purity.…”

Algorithm design of a Rubik metamaterial for sextuple orbital angular momentums

“…Vortex waves carrying OAM have the potential to improve the capacity of wireless communication systems beyond the limitations of Shannon's theorems 18 . Unlike conventional polarization converters, advanced converters require the adjustment of each element based on phased calculations 19 . As a result, a common strategy for fast deployment to create an efficient model is a promising area of research.…”

“…18 Unlike conventional polarization converters, advanced converters require the adjustment of each element based on phased calculations. 19 As a result, a common strategy for fast deployment to create an efficient model is a promising area of research. While some M&Ms can be created by arranging all elements of the same size or rotation, others such as vortex surfaces and beam scanning metamaterials, also known as phased M&Ms, require the adjustment of each element based on phased calculation.…”

Polarization properties of random electromagnetic vortex beam propagating in gradient‐index fiber

“…They open up numerous new and exciting possibilities in fiber optical communication, 8,9 wireless optical communication, 10,11 optical manipulation 12 . In recent years, partially coherent vortex beam also becomes a research hotspot in the academic community 13–17 . Compared with fully coherent vortex beams, partially coherent vortex beams have unique properties in physics and optics.…”

“…12 In recent years, partially coherent vortex beam also becomes a research hotspot in the academic community. [13][14][15][16][17] Compared with fully coherent vortex beams, partially coherent vortex beams have unique properties in physics and optics. Especially the joint regulation of its coherence and topological charge will lead to new properties, such as coherent singularities, 17 polarization state conversion, 18 and beam shaping.…”