Design and analysis of OAM based UCA for vehicular communications in 6G networks

Abstract This article presents the design and experimental validation of a uniform circular array (UCA) of circularly polarized (CP) slot patch antennas for generating orbital angular momentum (OAM) beams at 2.4 GHz. The proposed UCA configuration enables high-purity OAM beam generation with azimuthal symmetry, which is critical for vehicular communication applications. Using left-hand circularly polarized elements and a series-fed network, the UCA achieves precise phase control and minimal side-lobe levels. The antenna was optimized to produce the OAM mode with a topological charge l = 1. Numerical simulations and experimental measurements show that the design offers strong impedance matching and high mode purity, making it suitable for applications requiring conical beam radiation, such as vehicle-to-vehicle communications. The 3D measurements further validate the prototype’s effectiveness in generating OAM beams with symmetric radiation patterns, demonstrating significant azimuthal symmetry and confirming its applicability for dynamic vehicular environments.