A 28 GHz Beam Steerable Elliptic Microstrip Array Antenna for 5G Applications

This paper discusses the design, fabrication, and measurement of a two-layer, 2x10 elliptic, microstrip series fed antenna array operating at 28 GHz for 5G and mm-wave user equipment. A branch line coupler was used as a feeding network that can generate three beams. The peak gain value of each beam was 13 dBi at 28 GHz. The gain value was above 10 dBi within a beam coverage of -45 degrees to 45 degrees, and the peak gain value for the 26.5 GHz to 29.5 GHz band was above 10 dBi. The impedance bandwidth of the proposed design was below -10 dB in the 26.5 GHz to 29.5 GHz band. The dimensions of the 2x10 antenna array with coupler were 80x40x0.203 mm(3) on Rogers RO4003 substrate. This design is suitable for 5G mobile user applications due to its low cost and compactness.