Slot antenna array for fifth generation metal frame mobile phone applications

An eight-element antenna array based on open/closed slot modes that can cover the 3.5 GHz band (3400-3600 MHz) is proposed and studied. There are two kinds of antenna elements with the slot sizes of 10.8 x 1 mm(2) and 28.8 x 1 mm(2) for open and closed slot modes, respectively. Both the two kinds of antenna elements are realized with the help of the metal frames with the height of 7 mm at the two long sides of the ground. The proposed antenna array is suitable for 5G metal frame mobile phone applications. A prototype is fabricated and measured. The measured results show that all the eight antenna elements can cover the band of 3400-3600 MHz and the isolations are bigger than 13 dB, the measured efficiencies all are bigger than 42% and the measured envelope correlation coefficients are lower than 0.15.