Wideband 5G Millimeter-Wave MIMO Magnetoelectric Dipole Antenna Integrated With Partially Reflective Surfaces

A wideband 5G millimeter-wave multiple-input multiple-output (MIMO) magnetoelectric (ME) dipole antenna integrated with partially reflective surfaces (PRSs) is proposed. Each ME dipole consists of a planar electric dipole and an equivalent magnetic dipole. Owing to dual radiation modes of the ME dipole antenna, the wide bandwidth can be obtained. To increase the radiation gain, a dielectric slab with planar PRSs is placed over the ME dipole antenna. The PRS and the metal ground plane form a Fabry–Perot cavity, which can increase the radiation gain. Meanwhile, four dielectric cylindrical rings with rotationally symmetric PRSs can construct multiple Fabry–Perot cavities, and a further increase of the radiation gain can be obtained. The metal sidewalls and the polarization diversity are applied to reduce mutual coupling. The measured impedance bandwidth at −10-dB reflection coefficient is 24–43.5 GHz (57.8%). The measured transmission coefficients <inline-formula> <tex-math notation="LaTeX">$\vert {S}_{21} \vert $ </tex-math></inline-formula>, <inline-formula> <tex-math notation="LaTeX">$\vert {S}_{31} \vert $ </tex-math></inline-formula>, and <inline-formula> <tex-math notation="LaTeX">$\vert {S}_{32} \vert $ </tex-math></inline-formula> are less than −27, −37.9, and −46.4 dB, respectively. The simulated and measured maximum radiation gains are 17.3 and 16.1 dBi, respectively. Thus, the proposed 5G millimeter-wave MIMO ME dipole antenna integrated with PRSs features wide bandwidth, high isolation, and high radiation gain.