A Wideband Quasi-Yagi Antenna Array at 24–28 GHz for 5G mmWave Mobile Terminals

A wide-band quasi-Yagi antenna and its 4×1 array system proposed for mmWave 5G cellular terminal operating in the 24–28 GHz working band is presented. The antenna array is developed using a simple planar quasi-Yagi topology to fit into the 5G mobile terminals easily. A single antenna earnings a -10 dB impedance bandwidth for a reflection coefficient (S
11
) of 26% (23.28-30.29 GHz) and a gain of 7.65 and 8.37 dBi at 24 GHz and 28 GHz frequencies, respectively. Further, the two individual 4×1 linear quasi-Yagi antenna arrays are implemented at the top right corner of the mobile PCB. The array configurations can occupy an overall size of 66x46x0.254 mm
³
with 0.7λ
0
elemental spacing and having the -40 dB low mutual coupling obtained between the two 4×1 antenna arrays. The results show that the proposed two individual 4×1 linear quasi-Yagi antenna arrays have wide impedance bandwidth covering the 5G-n258 (24.25-27.5 GHz) frequency band and peak gains of 14 to 15 dBi at both 24 and 28 GHz frequencies respectively. With the broad hemispherical radiation characteristics and wider half power beam width, the proposed antenna arrays are a promising solution for 5G mmWave cellular terminals applications.