Eight-Port MIMO Slot Antennas with an EBG Reflector at Wi-Fi 5.8 and 6GHz Bands for Access Point Applications

The paper proposes a design of MIMO slot antennas with an EBG reflector at Wi-Fi 5.8 and 6GHz bands for access point applications. The design of MIMO antennas uses microstrip lines to excite four open square ring slots. The antennas and feeds are printed on FR4 substrate of loss tangent of 0.0245, dielectric coefficient of 4.4, and thickness of 1.6 mm. The overall dimensions of the design are 90 × 90 × 6.2 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup>. The EBG (Electromagnetic Bandgap) structure is formed by using 6 × 6 elements. The element is composed of 4 triangular patches. The overall size of the EBG is 90 × 90 ×1.6 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup>. The distance between the layer of antennas and the layer of EBG is 3 mm. It can effectively improve the isolation performance and reduce the overall height of the antenna. Therefore, this design is suitable for eight-port MIMO slot antennas at Wi-Fi 5.8GHz and 6GHz bands in access point devices.