Design and characterization of a compact single-layer multibeam array antenna using an 8 x 8 Butler matrix for 5G base station applications
Document Type
Article
Publication Date
1-1-2020
Abstract
A multibeam array antenna employing a Butler matrix is a promising solution for fifth generation (5G) base stations. Due to inaccurate phase differences between output ports in the Butler matrix, the radiation characteristics could show incorrect main beam directions. In addition, the literature has also reported the issue of high amplitude imbalance in the Butler matrix. This paper presents a single-layer multibeam array antenna fed by an 8 x 8 Butler matrix operating at 28 GHz for 5G base station applications-a more cost-effective solution for large-scale production. The Butler matrix consists of twelve quadrature hybrids, sixteen crossovers, and eight phase shifters. This circuit was integrated with eight antenna elements at the output ports of the Butler matrix. The proposed multibeam array antenna was fabricated using a low dielectric constant and a low loss tangent substrate. The dimensions of the multibeam array antenna were 88 x 106 x 0.254 mm(3). The Butler matrix achieved low insertion losses and low phase error with average values of 2.5 dB and less than +/- 10 degrees at 28 GHz, respectively. The measured return losses were less than -10 dB at 28 GHz. The measured radiation patterns were obtained and eight main beams were pointed at +/- 6 degrees , +/- 18 degrees , +/- 30 degrees , and +/- 44 degrees with measured gains between 9 dBi and 14 dBi.
Keywords
Base station, Butler matrix, Fifth generation, 5G, Multibeam array antenna, Single-layer
Divisions
sch_ecs
Funders
Universiti Malaya (BK043-2017)
Publication Title
Turkish Journal of Electrical Engineering and Computer Sciences
Volume
28
Issue
2
Publisher
Tubitak Scientific & Research Council, Turkey
Publisher Location
ATATURK BULVARI NO 221, KAVAKLIDERE, ANKARA, 00000, TURKEY