New Circular Array Configurations for Generating Orbital Angular Momentum (OAM) Beams

This paper proposes a simple and feasible scheme for generating orbital angular momentum (OAM) radio beams, i.e., sequentially rotating circularly-polarized (CP) elements in a circular array. First, the principle analysis is given to illustrate the OAM generation from the proposed scheme. Then, an actual circular array design, as well as simulation results consisting of four CP elements, is presented to validate the OAM generation. Compared to the previously reported research relating to OAM generation by phased circular arrays, the main advantage of our design consists in the more simplified and flexible design of the feeding network due to the reduction of inter-element phase shifters.