This paper investigates a low-profile Multiple Input Multiple Output (MIMO) antenna with enhanced gain based on Defected Ground Structure (DGS). The proposed antenna consists of two sets of four elements (2 x 2), and it is yielded at the central frequency of 5.5 GHz for Wireless Local Area Network (WLAN) applications. Being on RT5880 with height of 1.575 mm, the overall dimensions of MIMO antenna and single array are 145 x 88 x 1.575 mm3 and 75 x 82 x 1.575 mm3, respectively. To get high gain and low mutual coupling for antenna, a Defected Ground Structure (DGS) is proposed and integrated on ground plane. At 5.3 GHz, the gain of antenna achieves approximately 9.5 dBi while mutual coupling level is under -20 dB. Besides, the MIMO antenna witnesses a radiation efficiency of 93%. The measurement results are compared to simulation ones to verify the performance of the proposed antenna.
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