Reconfigurable Intelligent Surface Based Orbital Angular Momentum: Architecture, Opportunities, and Challenges

Orbital angular momentum (OAM) has gained a lot of attention due to its potential in enhancing the spectral efficiency for wireless communications. Using different OAM modes, multiple independent data streams are simultaneously transmitted by using spatial distribution helical phase, which enables as new form access technique Controlling phases incoming electromagnetic waves, reconfigurable intelligent surface (RIS) is suitable implementing OAM. In this article, an RIS-based framework introduced. The basic concepts and features RIS presented. Then classifications comparisons schemes summarized. Simulation results verify that transmission can achieve nearly 100 percent higher communication systems compared conventional scheme.