Dual-Band Eight-Antenna MIMO Array for 5G Smartphone

A compact dual-band antenna array for multiple-input multiple-output (MIMO) system in the smartphone is presented. Antenna elements in the array are set at the long side edge frame of the smartphone. The antenna has a planar structure with a compact size of 13.8 × 7 mm
²
(0.161λ × 0.082λ, λ is the wavelength at 3500 MHz) for operating at fifth-generation (5G) band (3400-3600 and 4800-5000 MHz). The total array consists of two symmetric four-antenna arrays, along two long side edge frame of the smartphone. A 2 mm (0.023λ) distance is achieved between adjacent antennas in each four-antenna array. The antennas have an acceptable isolation and thereof their envelope correlation coefficients (ECC) are less than 0.1 in the operating band.