Dual port disc monopole antenna for wide-band MIMO-based wireless applications

In this article, design and implementation of a wide-band dual port monopole antenna based on single circular disc radiating element has been presented for Multi Input Multi Output (MIMO) configured 4G mobile and wireless communication systems. The proposed antenna uses a partial ground plane with two rectangular grooves which lie exactly below the respective 50 microstrip feeding lines in order to obtain enhanced antenna's impedance bandwidth of 2-6 GHz. A circular cut with 14 mm radius and centered at intersection of two partial rectangular ground planes is etched to reduce port to port RF coupling. The implemented dual port monopole antenna on 1.575 mm thick RT/Duroid 5880 substrate (with =2.2, tangent loss=.001) provides >15 dB RF interport isolation for antenna's 10 dB impedance bandwidth of 2-6 GHz with measured gain variations of 2-6 dBi for each port excitation. In addition to interport isolation measurement for dual port antenna, the envelope correlation coefficient over the required frequency range has been calculated and plotted using S-11, S-22, and S-21 measurement results to endorse the performance of dual port implemented antenna for diversity applications.