Design of 2X2 MIMO patch antenna for multiband applications

Abstract

Multiple Input Multiple Output (2x2MIMO) patch antenna for multiband applications has been proposed by using groups of rings around the stepped cut at four corner and mid slot separation on the radiating path of the antenna. The proposed 2x2 MIMO patch antenna is simulated using Computer Simulation Technology (CST). The designed antenna was fabricated and the measurement was conducted to compare the simulated results with the fabricated results. The isolation bandwidth and efficiency are enhanced by using groups of rings around the stepped cut at four corner and mid slot separation on the radiating path of the antenna. The bandwidth of the proposed MIMO antenna from 1.4 GHz -2.5 GHz, and from 3GHz- 5.5 GHz are achieved. The rings used in this design are essential for having more new resonant frequencies. Beside that mid space separation on the patch is used to improve the isolation. However, coupling coefficients for the fabricated proposed antenna is below -20dB for the WiMAX (3.5GHz,5.2GHz and 5.5 GHz)application and under -15 dB for LTE(1.8GHz)and WiFi(2.4GHz) applications. Simulated diversity gain of the proposed 2x2 MIMO antenna system. 9.99 dB is achieved at the desired frequency bands. Envelope correlation coefficient (ECC) is less than 0.0005 at the desired frequency bands. This results implies that the proposed antenna system is suitable for MIMO applications. Radiation efficiencies of all desired frequencies are achieved above 70%. Hence the proposed 2x2 MIMO patch antenna can be used for LTE (1.8GHz), WiFi (2.4GHz), and WiMax (3.5GHz, 5.2 GHz and 5.5 GHz) applications.