In this paper, a 360° beam-steerable frequency-reconfigurable antenna with horizontal polarization is proposed. The antenna is based on an Alford loop and a parasitic circular array of tunable electric-LC (ELC) resonators. It is able to operate in either omnidirectional or directional mode allowing 360° beamsteering in the azimuth plane with an angular resolution of 18°. The frequency-tunable range is from 2.0 to 2.4 GHz (18.2% relative bandwidth). By introducing a 3-D printed dielectric lens radome and two plates with radial Vivaldi-shaped slots, the realized gain and front-to-back ratio (FBR) can be increased. The experimental characterization of an antenna prototype validates the design. The measured realized gain ranges from 6.2 to 8.2 dBi, and FBR is between 13 and 23 dB.
- Alford loop
- frequency reconfigurable antenna
- horizontally polarized antenna