A Wideband 3 dB T-Shaped Stubs-Loaded Coupler for Millimeter-Wave (mm-Wave) Beamforming Network Towards Fifth Generation (5G) Technology

This article presents a design of T-shaped stubs-loaded coupler for beamforming networks towards the fifth generation (5G) technology. The low-cost, lightweight and compact size of the wideband 3-dB T-shaped stubs-loaded coupler is proposed at 26 GHz. The symmetrical rectangular-shaped slots and T-shaped stubs are introduced in order to achieve the desired coupling values of 3 dB and 90° phase difference between output ports. Four symmetrical circular slots are loaded to retain the flatness of the differential phase characteristics between 24.75 and 27.25 GHz.