A Novel Double-Sided Printed Omnidirectional Antenna with Broad Bandwidth

This paper proposes a novel printed omnidirectional antenna. It consists of two FR4 dielectric substrates, each of which is printed on one side with different radiation units. Each radiating unit comprises two symmetrical monopole antenna arms, with the upper and lower radiating units forming a set of symmetrical dipole antennas. Additionally, the shape of each monopole is altered to enhance the radiation performance. The connection between the feedline and the arms is made by a stepped impedance converter to improve the broadband characteristics of the antenna. A gap is left between the top and bottom plates to introduce an air layer to improve the antenna radiation performance. The -10 dB bandwidth of the antenna simulation is 15.6% (from 2.66 GHz to 3.11 GHz, centered at 2.885 GHz), demonstrating excellent omni-directional radiation characteristics within this frequency range.