analyzing the effect of using electromagnetic metamaterials in the production of plane spiral orbital angular momentum waves (psoam)

The utilization of orbital angular momentum (oam) presents an effective approach that enables the simultaneous use of multiple channels on a single frequency. compared with conventional oam carrier waves—whose three-dimensional radiation pattern resembles a cone with a hollow region at its center—the planar-spiral orbital angular momentum (psoam) carrier propagates transversely, making it more suitable for various practical applications. for the first time, the generation of psoam waves using a uniform circular array of microstrip antennas based on electromagnetic metamaterials has resulted in a phase pattern distinct from the conventional oam theory. this study demonstrates that incorporating metamaterials into the antenna array structure facilitates the generation of higher-order oam modes with fewer elements than conventional antennas. simulation results indicate that the proposed array achieves approximately a 27% reduction in the number of antenna elements. furthermore, the introduced antenna exhibits a wide relative bandwidth of 1.93.