MIMO antenna with enhanced isolation elements for USB dongle applications

This paper proposes a PIFA type MIMO antenna at WLAN band for dongle application. The MIMO antenna consists of two identical PIFA antennas on both ends of an FR4 substrate and operates a frequency band at 2.45 GHz. A T-shaped element that is extended from system ground and a neutral line located on back side of the substrate are used to increase isolation between the two PIFAs. The neutral line is connected with the PIFAs through two connected holes. The isolation mechanism will be discussed in this article. The MIMO antenna occupies an antenna portion of 15 mm × 15 mm and a system ground of 15 mm × 40 mm. The overall dimension of 15 mm × 55 mm can be easily applied in the dongle element.