This paper presents a dual-band Multi-Input Multi-Output (MIMO) antenna design with acceptable isolation and compact size for wireless applications. The proposed antenna operates at two frequencies (2.75 GHz-5.3 GHz) and consists of two symmetrical monopoles with a T-shaped junction that is added on the upper layer of the substrate and used to connect the two monopoles and the ground plane. The T-shaped junction is added to enhance the isolation between the two antennas. Different forms of slots have been etched on the ground plane to adapt the frequency bands to the desired frequencies. The simulations and measurement are used to examine the performance of the antenna in terms of S parameters, radiation patterns and the envelope of correlation coefficient. The results show that the MIMO antenna has two resonance frequencies (2.75 GHz and 5.3 GHz), is suitable for WLAN applications and comes with a mutual coupling that is less than 12 dB. As a result, an envelope correlation coefficient lower than 0.001 and a diversity gain higher than 9.98 dB are obtained, which means that the antenna has a remarkable diversity gain at operating bands.
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