A Two-Element Slotted Cup-shaped Compact Monopole Antenna For MIMO Applications

A two-port MIMO antenna array with wideband and high decoupling characteristics for wireless systems operating in the frequency range extending from 2.9 to 4GHz covering 3.5 WiMAX bands is proposed. The antenna element consists of a slotted cup shaped monopole radiating element fed with $\mathrm{a}50 \Omega$ transmission line. The high isolation between the two elements is achieved by inserting a rectangular stub in the ground plane along with etching two DGS slots. The inserted DGS slots not only improve the isolation between the antenna elements but also improve the impedance matching and widen the operating band width. Besides demonstrating a small footprint of $26 \times 44 \times 1.6$ mm3, the proposed two-port MIMO antenna array has also shown a 10-dB impedance bandwidth of 26% (2.9-3.75 GHz), strong isolation of more than 22 dB, and good gain and efficiency of around 2.87 dBi and 98%, respectively, across the band of interest.