Study of Distributed Phased Array Antenna Array Spacing for 5G User Equipment

This paper focuses on the design of a distributed phased array (DPA) based on microstrip antennas for user equipment. First, an optimized microstrip antenna is designed to operate at 28 GHz with a maximum gain of 6.45 dBi. Followed by introducing characteristics of antenna arrays, array spacing (AS) is investigated as an important design parameter in DPA. A hybrid far-field radiation model is developed to study AS-induced impacts on overall DPA performance indexed by coverage efficiency (CE). Through the analysis, we find that certain ranges of AS lead to better performance. CE of the 2-layer DPA is studied and 95% or higher CE can be achieved when the minimum required gain is less than or equal to 8 dBi.