Exponential Flare Slot Vivaldi OAM Antenna for Near Field Communication in EVs and HEVs

This work presents the designing of 3D uniform circular array using eight exponential flare slot Vivaldi antenna elements that resonates in the frequency range of 3.68 to 5 GHz for generation of Orbital Angular Momentum (OAM) radio waves. Eight exponential flare slot Vivaldi antenna elements are placed in circular manner that form cylindrical arrangement. These elements are connected to a single coaxial cable at its center through a power divider network. All elements of circular array are fed with uniform amplitude and phase, to make progressive phase difference 0° for OAM mode 0. Similarly progressive phase difference -45° for OAM mode -1, and progressive phase difference 45° for OAM mode -1 has been simulated and results are presented. A prototype for the OAM (mode 0) in the above frequency range is fabricated and measured. The hardware results obtained through testing of the array provide are closer to the simulated results. For OAM mode 0, four-element antenna array is also simulated to check the mode purity and results are discussed with 8-element antenna array. The beam divergence of proposed high capacity OAM antenna can be utilized in EVs and HEVs.