3-D-Printed Wideband Circularly Polarized MIMO Dielectric Resonator Antenna
Chen Yang, Kwok Wa Leung
Abstract
A 3-D-printed wideband circularly polarized (CP) multiple-input–multiple-output (MIMO) antenna is proposed. This antenna consists of two CP dielectric resonator antennas (DRAs) which are covered by a dielectric decoupler. With this decoupler, the center-to-center distance between the two DRAs can be made as small as <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.33\lambda _{0}$ </tex-math></inline-formula> with a high isolation, where <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\lambda _{0}$ </tex-math></inline-formula> is the operating wavelength in air. To verify the simulation, a prototype operating in X-band was designed, fabricated, and measured. Its measured −10-dB impedance bandwidth is 21.7% (8.88–11.04 GHz), within which the axial-ratio (AR) bandwidth and mutual coupling are less than 3 and −21.4 dB, respectively. The impedance and AR have a wide overlapping bandwidth of 21.7%.