An Ultra-wideband Reflectarray Antenna Using Connected Dipoles for Multifunctional Systems

A novel ultra-wideband reflectarray antenna using connected dipoles for multifunctional systems is proposed in this paper. The reflectarray element is composed of an elliptical dipole and a slot line which are printed on a single substrate. Neighboring elements are connected to achieve the ultra-wide bandwidths for both the impedance and the radiation pattern bandwidths simultaneously. By combining the advantages of conventional reflectarray antennas and connected array antennas, the proposed reflectarray antenna achieves ultra-wide bandwidth with greatly reduced feeding complexity and fabrication cost. As a proof of concept, a 354-element reflectarray antenna is designed. The presented reflectarray antenna maintains undistorted beams and high antenna gain over a bandwidth of 100%, i.e., from 10 to 30 GHz.