Quad-band dual-port MIMO microstrip antenna with double integrated circularly polarized bands for 4G/5G wireless applications

A quad-band two-port MIMO antenna is presented with four operating bands at 2.4, 3.5, 5.8, and 8.2 GHz to serve WLAN, 4G LTE, 5G & ITU applications, respectively. The wide impedance bandwidth of 13.33% (2.28-2.60 GHz), 21.62% (2.98-3.74 GHz), 8.9% (5.58-6.10 GHz) and 4.8% (8.00-8.44 GHz) is achieved at respective operating bands. The antenna also provides circular polarization at 3.5 GHz and 5.8 GHz. It is fabricated on FR4 substrate of 50 x 76 x 1.6 mm3 dimensions. The isolation between both ports is below 28 dB within all four operating bands. The radiation efficiency is about 90% in the first two bands whereas it is about 75% in the remaining two bands. The presented MIMO antenna shows better radiation characteristics along with satisfactory diversity performance. Experimental results of the fabricated prototype validate the simulated results.