Broadband antenna array with low cost PCB substrate for 5G millimeter wave applications

In this paper, a novel broadband antenna array is presented. The radiating element is a unique via-fed U-shaped patch element with a distribution network based on offset stripline technology. The feed position has been deliberately designed for optimized matching taking into account the design rules of a low cost PCB mass production technology. The radiating element has a 3-dB beam-width of ±30 degrees in both planes making it suitable for beam steering. To show the validity of the approach, a 2×2 array prototype is presented in this paper. The antenna array is approximately 12mm×12mm in size realized on a Rogers 4350 substrate. The antenna has been optimized for the 24-34 GHz frequency range. Simulated and measured return loss, radiation pattern and gain over frequency have been presented. This antenna structure is a good candidate for steerable phased arrays in 5G millimeter wave applications.