A Compact Phase-Controlled Pattern-Reconfigurable Dielectric Resonator Antenna for Passive Wide-Angle Beam Scanning

The function of passive wide-angle beam scanning is desired by the base station antenna to provide “green” cellular services. In this communication, such function is realized by designing a compact phase-controlled pattern-reconfigurable dielectric resonator antenna (DRA). The proposed DRA has a compact structure with a side length of $0.38 \boldsymbol {\lambda }_{\text {c}}$ and excites the fundamental TE and TM modes by diverse ports. By assigning phase between diverse ports, E-plane tilted patterns are synthesized with ±66° scan angles. Its pattern-reconfigurable capability makes contributions for increasing array beam scanning angle and minimizing gain fluctuation. A passive four-element array is verified to have an enhanced beam scanning angle of ±81° with a gain fluctuation of 1.25 dB. The maximum gain of the scanning beam is located on the off-axis angle of ±66° and achieves a wide 3 dB scan coverage of ±105°. Good agreements have been shown between the measured and simulated results. The proposed phase-controlled pattern reconfigurable DRA and DRA arrays have an impedance bandwidth of 3.33% (2.95–3.05 GHz) for a sub-6 GHz wireless system. They enable the wide-angle beam scanning for base station antenna and provide a cost-effective passive system for “green” communications.