An eight-element multiple-input-multiple-output antenna system which consists of H-shaped slot antennas is presented around the handset frame for 5G applications. Each antenna element consists of a H-shaped radiating surface and an L-shaped microstrip feeder. In the frequency bands of 3.4-3.6 GHz and 4.7-5.1 GHz, the isolation is lower than -15 dB by introducing the ladder-shaped defect ground structure. The antenna efficiency is 50%-81%, and the envelope correlation coefficient is lower than 0.02 among antenna elements. The measurement results agree well with the simulation ones, indicating that the proposed antenna can satisfy the requirements of 5G communication.
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