A novel four-element multiple input multiple output (MIMO) antenna system for LTE 2300 and 2.45 GHz ISM applications is presented. The total size of the proposed MIMO antenna system is 34 mm×18 mm, and the whole antenna system has a wide working bandwidth of 350 MHz (2.19-2.54 GHz). The measured isolation between antenna elements is higher than 15 dB with a close edge-to-edge separation of 0.03λ. Correlation coefficient of the MIMO antenna system is lower than 0.12, which can meet the requirements of 4G wireless systems.
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