A Rotman Lens Excited DRA Array for Generating Multiple PSOAM Modes at Ka-Band

This paper presents the generation of multiple plane spiral orbital angular momentum (PSOAM) modes in a uniform circular dielectric resonator antenna (DRA) array configuration. In order to generate multi-mode PSOAM waves, the antenna elements are fed by a $13 \times 16$ Rotman lens which provide thirteen different feeding schemes. The proposed antenna array can be able to generate $\pm 1, \pm 2, \pm 3, \pm 4, \pm 5, \pm 6$ PSOAM modes simultaneously at Ka-band.