FR4 PCB grid array antenna for millimeter-wave 5G mobile communications

Future broadband mobile communication networks such as 5G and beyond will most likely use millimeter-wave frequencies. There is, however, little knowledge about millimeter-wave antenna design for cellular mobile devices. This paper reports a microstrip grid array antenna on an FR4 substrate in a standard PCB technology. It is shown that the microstrip grid array antenna covers a footprint of 15×15 mm2, radiates a fixed beam in the boresight direction, and achieves the 10-dB impedance bandwidth of 7.16 GHz from 23.86 to 31.02 GHz and the 3-dB gain bandwidth of 4.79 GHz from 27.54 to 32.33 GHz with the maximal realized gain of 12.66 dBi at 29.2 GHz.