Design of MIMO Antennas for WiFi/5G Small Cell Applications

In this paper, a 4×4 MIMO antenna for small cell is presented. The proposed antenna operates at the WiFi 2.4/6E (2400~2484 MHz, 5000~7125 MHz) and 5G (3300~5000 MHz) bands. In order to excite these three bands with omnidirectional radiation and good isolation, the antenna consists of two vertical and a horizontal substrates. The vertical structure is operated at WiFi bands and is composed of PIFA and monopole antenna. The horizontal one is an element of 5G band and made up of four slot antennas with a 90 degree phase difference. Then two vertical substrates are cross-soldered to the horizontal one, a 4×4 MIMO antenna is obtained. In this way omnidirectional radiation and good isolation can be achieved. The final antenna has an overall size of 120 × 120 × 24.8 mm
³
. Experimental results are in good agreement with simulated values.