A compact OAM antenna for generating CP radiation patterns of three modes by using half‐mode SIWs

Abstract Based on a uniformly sequential rotational array, this study proposes a compact orbital angular momentum (OAM) antenna, for generating circularly polarized radiation patterns of three modes. The antenna consists of four half‐mode substrate integrated waveguides and has a diameter of one wavelength in free space. Both the simulation and the measurement results show that the proposed antenna can generate ±1 OAM modes with circularly polarized radiation patterns with a gain of 9.2 dBi. The antenna can also generate 0 OAM mode with a conic radiation pattern with a gain of 7.0 dBi. The compact OAM antenna with three modes can be applied in multiplex systems with strict requirements on aperture dimensions.