Orbital Angular Momentum (OAM) is an attractive feature of electromagnetic waves that gains great research attention in several areas in radio and optics. This paper describes a superposition of OAM waves of different orders for single/multi-beam steering in the transverse direction in communication and radar-sensing applications. A new design of the antenna is proposed. The main body of the antenna consists of a concentric circular loop antenna array that is excited by a traveling wave current. This design overcomes some of the limitations challenging the use of multi-orders OAM waves in beam steering, in particular the need for placing more than one OAM-order generator in the same plane. The proposed method overcomes this limitation as many loops of different sizes could be simply placed in one plane. The feeder of the antenna, on another hand, is designed using two loops with one being a parasitic element. This parasitic element-based design shows great enhancement to the bandwidth allowing the antenna to serve over a wide range of applications. Various OAM mode groupings using the superimposed OAM waves are demonstrated here via theoretical calculations, and beamforming is validated with full-wave numerical simulations.

轨道角动量（OAM）是电磁波的一项引人注目的功能，在无线电和光学的多个领域都引起了广泛的研究关注。本文描述了在通信和雷达传感应用中，用于横向单/多波束转向的不同阶次OAM波的叠加。提出了天线的新设计。天线的主体由同心圆环形天线阵列组成，该阵列由行波电流激发。这种设计克服了在束控制中使用多阶OAM波挑战性的一些局限性，特别是在同一平面上放置多个OAM阶发生器的需求。所提出的方法克服了该限制，因为可以将许多不同大小的回路简单地放置在一个平面中。另一方面，天线的馈线 采用两个回路设计，其中一个为寄生元件。这种基于寄生元件的设计显示出带宽的极大提高，从而使天线可以在广泛的应用中使用。这里通过理论计算演示了使用叠加的OAM波的各种OAM模式分组，并通过全波数值模拟验证了波束成形。