2×2 MIMO antenna at 2.4 GHz for WLAN applications

Multiple Input Multiple Output (MIMO) techniques have merged as a key technology for the next generation wireless communication systems because they enable very high data rate transmission. Unlike the Single Input Single Output (SISO) systems MIMO systems enhance the capacity and data rate of wireless transmission. In MIMO multiple antennas are used at the transmitter and receiver sections. This paper discusses the design and simulation of a two-element MIMO antenna which can be used for WLAN applications. The MIMO antenna system consists of two radiating elements on a single low-cost FR4 substrate with a thickness of 1.6mm. The proposed antenna operates at 2.4 GHz. The bandwidth of the antenna is 60MHz, which extends from 2.38GHz to 2.47 GHz which is suitable for WLAN operations. The distance between the two antenna elements is 3mm (0.05λ). The gain of the designed antenna is around 7dB. Defected Ground Structure (DGS) has been added on the ground plane of the antenna to enhance isolation between the two radiating elements. Isolation between the two radiating elements could be decreased upto -20dB from -13 dB with the use of defected ground structure. The design and simulation has been carried out in ANSOFT HFSS software. Antenna has been fabricated and testing for return loss was performed using Agilent N5230A Network Analyzer.