Reconfigurable grounds MIMO antenna with PIN diodes for 5G NR n3/n1/n40/n41/n77/n79 to X-bands

Abstract

ABSTRACT The paper addresses the investigations of four elements MIMO antenna with reconfigurable grounds for 5 G NR n3/n1/n40/n41/n77/n79 to X-bands using PIN diodes. Initially, a single unit ultra wideband antenna is implemented, and then it is extended to 2 × 2 MIMO with reconfigurable grounds using one PIN diode. Later, the 4 × 4 MIMO antenna with reconfigurable grounds using six PIN diodes is developed. This study has the novelty that it gives the analysis and design of MIMO antennas switching between unconnected and connected grounds by the method of reconfiguration. The proposed 4 × 4 MIMO is fabricated on FR4 substrate with a volume of 0.485λ0 × 0.326λ0 × 0.0075λ0 mm3, where λ0 is calculated at a lowest resonating frequency. It has operating frequency bands of 1.4–1.6 GHz, 1.75–2.5 GHz and 2.7–13 GHz with connected grounds. The port isolation in the majority of the band is ≤ −15 dB. The inference is included on all the performance metrics. The fabricated MIMO performance is in line with simulated results and hence validates the observations of this research work. So, the proposed MIMO designs are compatible with 5 G wireless applications.