Analysis and Optimization of a Compact 1x4 Array Antenna for 5G Application

This paper presents a 1x4 broadband array antenna which designed on a 10 (4+2+4) multi-layer organic substrate. The array antenna has a compact size of 27 x 4.5 mm2, and is suitable for the 5G mmWave mobile devices. In order to achieve the compact size and broadband performance, the shorted parasitic elements are added around the stacking patch antenna. The shorted parasitic element includes the shorted-wall and the parasitic element. The parasitic element adds the shorted-wall structure to achieve the grounding effect, which can reduce half of the component area. The antenna size is down 33 % from 6.75 x 6.75 mm2 to 6.75 x 4.5 mm2. However, compared with adding traditional parasitic patch, the antenna bandwidth maintains around 4.1 GHz (25.75 - 29.85 GHz). The simulated gain of the 1x4 array antenna is 10-10.88 dBi in the operating bandwidth. The 1x4 array antenna has the advantages of broadband and compact size, making it is an attractive solution for 28 GHz mmWave bands in mobile devices.