Multimode OAM Beams Generation using Concentric UCA for Future Large-Capacity Wireless Communication Systems

The unique phase distribution characteristics in the radio beams carrying Orbital Angular Momentum (OAM) can be utilized to build large-capacity future wireless communication systems. In this paper, the concentric Uniform Circular Array (UCA) comprising three circular arrays of identical rectangular patches for generating multimode OAM beams is presented, which can certainly be utilized to improve the data rate and spectrum efficiency in future wireless communication systems. The array is designed to operate at 5 GHz Wi-Fi applications for short-distance communication. It can transmit 0, ±1, ±2, and ±3 OAM modes simultaneously in free space with a realized gain of 9.3 dB, 10dB, 11.6dB, and 12 dB, respectively. Because of the inherited orthogonality property in the various OAM modes, these OAM modes can be used in spatial multiplexing with good isolation between the adjacent modes.