Diagonally Shielded HMSIW-Based Self-Triplexing Radiating Element for 5G Wireless Applications

A compact self-triplexing antenna (STA) operating simultaneously at 5.25 GHz, 28.85 GHz, and 31.9 GHz with better than 33 dB isolation among the frequency bands is presented in this letter. The design is based on a diagonally shielded half-mode substrate integrated waveguide cavity, which is designed by placing an open rectangular slot along the diagonal perfect magnetic wall and a row of metallized vias in a square cavity to shield the RF leakage. The cavity is loaded with two orthogonal modified rectangular slots on its top surface to facilitate triplexing operation. The STA features input reflection better than −10 dB over a fractional bandwidth of 3.79%, 4.16%, and 3.29% at 5.25 GHz, 28.85 GHz, and 31.9 GHz, respectively. The proposed STA has a peak gain of 5.1 dBi, 8.1 dBi, and 8.3 dBi with good cross-polarization levels at 5.25 GHz, 28.85 GHz, and 31.9 GHz, respectively. The STA achieves an efficiency better than 80% and 90% in microwave and mm-wave frequency regimes, respectively. The proposed STA is modeled and fabricated, and simulated results are experimentally validated.