Omnidirectional conformal microstrip array antenna with electronically beam switching capabilities for 5G applications

Abstract

This article presents an omnidirectional and electronically beam switching conformal microstrip array antenna at 3.5 GHz frequency for 5G applications. The 1×2 array microstrip antenna is used as a radiating element. It is placed on a hexagonal shape-holding structure to form the conformal geometry. The radiating elements are excited by a six-faced feeding network. It consists of one 3-way power divider and two 2-way power dividers. These power dividers are serially connected and form a six-faced regular structure with 12 output ports. The output ports of the uniform power divider feed network are connected to the conformal array and provide the omnidirectional radiation pattern. To obtain the beam switching mechanism, the uniform power divider is then loaded with an RF switched power divider and connected to the conformal array. Six angular separation beams (Sector I to VI) are obtained (60°) with RF switches. The response of the feed network along with the radiating element is verified experimentally. The impedance bandwidth is well below <−10 dB and measured isolation among different output ports are below −20 dB. The simple microstrip design technique makes the antenna suitable for omnidirectional and beam switching in a large array configuration for 5G applications.