Generation and Transmission of OAM-Carrying Vortex Beams Using Circular Antenna Array

Electromagnetic orbital angular momentum (OAM) has attracted a lot of interest recently in the field of communication systems. OAM-carrying radio beams can be generated and detected by several devices. In this paper, we use a circular phased antenna array to generate OAM-carrying beams that possess ring-shaped intensities and helical phase fronts. We also propose and validate a communication system that uses OAM-based multiplexing. A circular antenna array is used to generate the superimposed OAMmode by using appropriate excitation settings. The transmission characteristics of OAM modes with respect to different transmission distances are investigated. We find that the OAM-based multiplexing technology is only feasible within a certain distance range. The obtained experimental results are consistent with simulation and numerical calculation results.