Mutual Coupling Reduction & Bandwidth Enhancement Using a Simple Folded Slot-Partial Ground Plane in Dualband MIMO Antenna

This paper presents a simple technique to enhance the bandwidth and reduce the mutual coupling in dualband MIMO planar monopole antenna. We use a combination of simple folded slot and partial ground plane. The proposed MIMO antenna structure consists of two planar monopole elements which are arranged side by side on a compact FR4 substrate with dimensions 30×50×1.6 mm
³
, The existing of the folded slot in patch radiator causes a changing of operation frequency to be two frequencies bands/dualband, i.e., 2.8 GHz/lower frequency and 3.5 GHz/upper frequency. These two frequency bands are addressed to implement 5G mobile communication in Indonesia. According to the simulated results, our technique yields a refinement of mutual coupling approximately 4 dB at upper frequency. In addition, partial ground plane improves a wider impedance bandwidth (S11, S22 <; - 10 dB). The improvement of impedance bandwidth values are 9.22 % (antenna 1) & 45.1 % (antenna 2) at lower frequency and 1.19 % (antenna 1) & 42.9 % (antenna 2) at upper frequency, respectively. The obtained envelope correlation coefficient (ECC) values show that partial ground plane also gives a better ECC than full ground plane and its numerical values are less than the MIMO threshold value of 0.3.