A New Antenna Capable of Generating Broadband Plane Spiral Orbital Angular Momentum

Abstract

The plane spiral orbital angular momentum (PS-OAM), which is a special form of orbital angular momentum (OAM) beams, solves the problem of OAM beam divergence to some extent. The majority of OAM antennas can only generate vortex beams in a narrow band range, which severely limits their broadband application potential. This study proposed a single antenna that can produce PS-OAM beams in the 8-16 GHz frequency range. The antenna is composed of six Vivaldi antennas placed in a tangential circular array, and the ports of the neighboring Vivaldi antenna elements exhibit phase difference. When fed with equal phase and amplitude, the antenna can generate broadband PS-OAM beams with mode +2. In contrast to current OAM antenna arrays fed with phase-shifting, the suggested antenna is straightforward and simple to feed. The proposed Vivaldi antenna based on UCA may provide a new way for generating broadband OAM beams.

Keywords

• Plane spiral orbital angular momentum (PS-OAM)
• Vivaldi antenna
• phase errors
• circular array
• broadband antenna