Ultra-wideband antenna with single- and dual-band notched characteristics based on electric ring resonator

The ultra-wideband (UWB) monopole antenna is designed as the circular patch fed by a coplanar waveguide (CPW). To achieve the notched characteristics at desired frequencies, the electric ring resonator (ERR) incorporated into the CPW feed line is used. The notched frequency band is controlled by dimensions of the ERR structure. The single-notched band is obtained by placing a single-mode ERR beneath the CPW structure. For implementation of the dual-notched band, either a cascaded connection of different ERRs or a modified structure of the dual-mode ERR can be used. Four band notched UWB antennas were prototyped and measured. The results of simulations and measurements are in a good agreement.