Metasurface Antenna for Fast Frequency Scanning With Application to Conical Direction Finding

Abstract

The functionality of a metadome to provide fast frequency conical beam scanning using a simple feeding is reported in this letter. A metasurface composed of periodic patches covering a simple monopole antenna acts as a partially reflective sheet to produce frequency-scanned conical beams. Then, the addition of a high-impedance surface in the ground plane is used to increase the scanning ratio. This is important to cover a wide scanning range using a narrow frequency bandwidth. A design example for conical direction finding with a field of view of 60° and using the 200 MHz unlicensed band from 5.1 to 5.3 GHz, is demonstrated with a metadome antenna prototype.