A MIMO antenna system with high isolation for smart phone applications

In this paper a new compact planar monopole-like multiple-input-multiple-output (MIMO) handset antenna is proposed. The antenna system consists of two identical antennas with a defected ground arrangement for low correlation and high isolation characteristics. The antennas are oriented horizontally at the no-ground portion located at the top and bottom of the FR4 50 χ 102 mm2 circuit board. The proposed system operates at the 2.3 GHz (2.13-2.64 GHz), 3.6 GHz (3.11-4.83 GHz), and 5.6 GHz (5.15-7.62 GHz) bands. The isolation maintained is better than 18 dB over the desired frequency bands, resulting in an envelope correlation coefficient of less than 0.025. The simulated and measured S-parameters show good agreement. Due to the compact size, the proposed MIMO antenna system is suitable for smart phone applications that have size limitations.