Dual-Band (28/38 GHz) Wideband MIMO Antenna for 5G Mobile Applications

A dual-band wideband composite patch antenna constructed from a modified circular primary patch and secondary parasitic patch element is presented in this work. A microstrip feed line is employed to inset-feed the primary patch. The secondary patch is fed indirectly through edge coupling with the main patch. The composite antenna is printed on Rogers Ro3003 (TM) with epsilon(r) = 3 and thickness 0.25 mm. The antenna design stages are presented in detail. A MIMO antenna system is constructed from two elements of the proposed composite patch with two different configurations. A prototype is fabricated for the single element and the two-port MIMO antenna configurations. Numerical and experimental results are presented showing good performance regarding impedance matching at the operating bands 28 and 38 GHz, bandwidth, radiation patterns, and gain. The impedance matching bandwidths are 1.23 GHz at 28 GHz and about 1.06 GHz at 38 GHz. The minimum value of the reflection coefficient for 28 GHz 28 GHz band is -34.5 and is -27.3 dB for 38 GHz. The gain of the radiation pattern has a peak of 6.6 dBi at 28 GHz and 5.86 dBi at 38 GHz. For both bands, the radiation patterns are balloon-like omnidirectional. The antenna total dimensions are 7.5 x 8.8 x 0.25 excluding the transmission line. The MIMO system with two-ports for both proposed configurations has appropriate values for ECC and the DG which are calculated through electromagnetic simulations.