Diversity/MIMO Antenna Incorporating Electromagnetic Band Gap Structures for Isolation

A miniaturized two element multiple-input-multiple- output (MIMO) antenna for Ultra Wideband (UWB) communication system is proposed in this paper. The proposed design contains semi-circular shaped antennas with notched corners. The impedance match has been improved by employing the tapered feed lines and ground structure. The antenna elements exhibit an impedance match S11/S22 < -10 dB, over entire frequency band from 3 to 12 GHz. Enhanced isolation is achieved with an electromagnetic band gap (EBG) decoupling structure with circular and rectangular stubs is designed to achieve isolation between MIMO elements. This EBG structure provides an isolation of more than 22 dB for whole UWB frequency band. The UWB MIMO antenna array proposed in this paper has dimensions of 22 × 55 mm2. The simulated as well as measured results proposes that the diversity/MIMO array can be used for portable Ultra-wideband applications.