Broadband Generation Orbital Angular Momentum Beams Based on Uniform Phase Error Analysis of Uniform Circular Array

In this paper, we propose a method for generating broadband orbital angular momentum (OAM) beams utilizing the two neighboring ports of the uniform circular array (UCA) excited with a phase difference of (2( pi + delta )l )/N . This approach differs from current arrays used to generate an OAM beam with a phase difference of 2 pi l /N . We establish that the UCA can produce OAM beams covering 83% (7-17 GHz) of the bandwidth. The array antenna consists of three Vivaldi elements with a phase difference between adjacent ports, capable of generating OAM beams of mode 2 when being fed with equal amplitude and phase. In contrast to current OAM antenna arrays that require complex phase -shifting networks for feeding, our proposed antenna array offers simplicity in its feeding mechanism. Furthermore, the UCA-based Vivaldi antenna presents a novel approach for generating wideband OAM beams and holds significant potential for applications in broadband communication.