Wideband Three-Port Equilateral Triangular Patch Antenna Generating Three Uncorrelated Waves for 5G MIMO Access Points

A wideband three-port equilateral triangular (ET) patch antenna capable of generating three uncorrelated broadside-radiation waves for 5G MIMO access-point application is presented. The three-port ET patch antenna has a simple structure for easy implementation. To our best knowledge, using a simple ET patch antenna to generate three uncorrelated waves for MIMO application is reported for the first time. The ET patch is mounted 11.5 mm above the ground plane and has three L-strip capacitive feeds placed below the patch’s three triangular tips. Three isolated fundamental TM
₁₀
modes polarized in three different directions can be excited to generate three uncorrelated waves at the same time. With a patch length of only 38 mm (
$0.48\lambda $
at 3.75 GHz), the three-port ET patch antenna covers 3.3-4.2 GHz (5G N77 band) with impedance matching < −10 dB and port isolation >15 dB. Details of the three-port ET patch antenna are presented.