Two-ray multipath propagation of MIMO-based OAM radio communications

Orbital angular momentum (OAM) has attracted considerable attention as a novel solution for wireless communications for orthogonal eigenmodes. However, most researches focus on line-of-sight (LOS) scenario. In practice, multipath effects are inevitable in wireless communication. Hence, this paper investigates and analyses the multipath effects in OAM-multiple-input-multiple-output (MIMO) communication system. Numerical results show that multipath effect brings distorted rotating phase-front and results in intra-channel crosstalk, while multipath effects increase as the diverging of the OAM-carrying wave in higher OAM eigenmodes.