LAUSR

A low-profile planar four-element MIMO antenna is proposed in this paper that can be integrated inside wireless handheld devices. Every unit antenna is made of simple planar L-shaped monopole placed over etched non-ground area of 10 × 5 mm 2 . The optimized antenna elements cover three 5G New Radio bands falling within C-band: n77 band (3.3–4.2 GHz), n78 band (3.3–3.8 GHz) and n79 band (4.4–5 GHz), with isolation better than 18.8 dB, without the requirement of any additional decoupling structure. The designed antenna is fabricated on FR4 substrate of dimension 120 × 65 × 1.6 mm 3 . Antenna characteristics regarding reflection coefficient, mutual coupling, radiation pattern and gain are measured and discussed. The envelop correlation coefficient is computed and is lower than 0.018 for the entire range of frequency under consideration. The simplicity and compactness of the proposed MIMO antenna provides adequate space for integration of other circuits inside handheld mobile terminal. Further the integration with lower generation antennas are investigated; the result indicates that the placement of the proposed antenna system on the two long arms of ground plane offer adequate space for integration of lower generation antenna without adversely affecting each other’s performance.