Two Monopole Antennas for Generating Radio OAM Waves in Circular Waveguide

International audienceWe present a novel way to generate waves bearing Orbital Angular Momentum (OAM) in a circular waveguide by using two monopole antennas. The OAM mode l = 1 is generated by a combination of the classical TM01 and TE21 modes of the circular waveguide. Two printed monopole antennas are used to create these two modes. The design procedure of this novel "OAM antenna" is presented. The resulting electrical field distribution and the radiation and phase patterns evidence the properties of waves bearing OAM. Index Terms-orbital angular momentum, circular waveguide, monopole antenna