Dual-Beam Antenna for Millimeter Wave MIMO Applications

A dual-beam multiple-input-multiple-output (MIMO) antenna is proposed for next-generation wireless communication. Each antenna is an array of two dipole antennas separated by a distance of about $\boldsymbol{\lambda}_{\boldsymbol{d}}$ (wavelength in dielectric at 30 GHz) to generate dual-beam radiation pattern in the end-fire direction. The two antennas are arranged in a small space and each antenna covers 27 to 33 GHz band with $\mathbf{S}_{\mathbf{ii}} < -10$ dB and $\mathbf{S}_{\mathbf{ij}} < -28\ \mathbf{dB}$. The proposed antenna can cover a large radiation area owing to pattern diversity with radiation along $\boldsymbol{\phi}=60^{\mathbf{o}}$ and $\boldsymbol{\phi}=120^{\mathbf{o}}$ when port 1 is excited and along $\boldsymbol{\phi}=150^{\mathbf{o}}$ and $\boldsymbol{\phi}=210^{\mathbf{o}}$ when port 2 excited. Both antennas have dual-beam radiation pattern in the azimuthal plane with a peak gain of 9 dBi essential for millimeter wave MIMO communication.