Dual Band-Notched Rectangular Dielectric Resonator Antenna with Tunable Characteristic

A dual band-notched reconfigurable dielectric resonator antenna (DRA) is proposed in this paper. A rectangular dielectric resonator excited by stepped offset microstrip feedline generates multiple resonant modes for wideband performance. Moreover, the typical stepped impedance feedline and partial ground plane with one rectangular notch are adopted for contributing for better impedance matching. On this basis, a five-line coupler resonator (FLCR) composed by inverted U-shaped and 山-shaped structures is introduced as a bandstop filter in the microstrip feedline, and dual rejected bands are created. Tunable notched frequencies are achieved by the varactor between these two structures. The proposed antenna size is 24 × 28 × 5.637 mm3. For the presented work, both simulated and measured results for the proposed tunable antenna ranging from 5.3 to 5.84 GHz and from 8.74 to 8.98 GHz within the wide bandwidth of 6.06 GHz are presented, demonstrating the accuracy of this design. There capabilities make the proposed antenna applicable for wideband systems with the requirement of avoiding interferences.