A Novel Liquid Crystal Phase Shifter Enhanced Butler Matrix Topology for Continuously Steerable 60 GHz Antenna Array

Onur Hamza Karabey

doi:10.54287/gujsa.1832327

A Novel Liquid Crystal Phase Shifter Enhanced Butler Matrix Topology for Continuously Steerable 60 GHz Antenna Array

Abstract

In this paper, a continuously steerable 1x4 antenna array operating at GHz is presented. Traditional Butler matrix networks provide discrete beam steering, limiting their flexibility for modern high data rate millimeter-wave applications. To overcome this limitation, a novel hybrid topology is proposed in which tunable liquid crystal (LC) phase shifters are integrated into the Butler matrix. This configuration enables smooth and continuous beam steering across the angular range without relying on complex control schemes or mechanical movement. A key advantage of the proposed design over conventional LC-based phased arrays is the significantly reduced phase shift requirement. Thanks to the directional biasing introduced by the Butler matrix, only of differential phase shift is needed from the LC elements to achieve full angular coverage by interpolating between Butler-defined beam directions. The LC phase shifters are optimized for GHz operation and integrated seamlessly into the network without degrading broadband characteristics. Simulation results validate continuous beam steering over maintaining low sidelobe levels and flat gain, making the design well-suited for dynamic GHz communication systems.

Keywords

References

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Details

Primary Language

English

Subjects

Radio Frequency Engineering, Antennas and Propagation, Wireless Communication Systems and Technologies (Incl. Microwave and Millimetrewave)

Journal Section

Research Article

Authors

Onur Hamza Karabey ^*
0000-0001-5283-6107
Türkiye

Publication Date

March 31, 2026

Submission Date

November 29, 2025

Acceptance Date

February 20, 2026

Published in Issue

Year 2026 Volume: 13 Number: 1

DOI

https://doi.org/10.54287/gujsa.1832327

IZ

https://izlik.org/JA39ZZ84CZ

Cite

RIS / Bibtex

APA

Karabey, O. H. (2026). A Novel Liquid Crystal Phase Shifter Enhanced Butler Matrix Topology for Continuously Steerable 60 GHz Antenna Array. Gazi University Journal of Science Part A: Engineering and Innovation, 13(1), 215-228. https://doi.org/10.54287/gujsa.1832327

AMA

1.Karabey OH. A Novel Liquid Crystal Phase Shifter Enhanced Butler Matrix Topology for Continuously Steerable 60 GHz Antenna Array. GU J Sci, Part A. 2026;13(1):215-228. doi:10.54287/gujsa.1832327

Chicago

Karabey, Onur Hamza. 2026. “A Novel Liquid Crystal Phase Shifter Enhanced Butler Matrix Topology for Continuously Steerable 60 GHz Antenna Array”. Gazi University Journal of Science Part A: Engineering and Innovation 13 (1): 215-28. https://doi.org/10.54287/gujsa.1832327.

EndNote

Karabey OH (March 1, 2026) A Novel Liquid Crystal Phase Shifter Enhanced Butler Matrix Topology for Continuously Steerable 60 GHz Antenna Array. Gazi University Journal of Science Part A: Engineering and Innovation 13 1 215–228.

IEEE

[1]O. H. Karabey, “A Novel Liquid Crystal Phase Shifter Enhanced Butler Matrix Topology for Continuously Steerable 60 GHz Antenna Array”, GU J Sci, Part A, vol. 13, no. 1, pp. 215–228, Mar. 2026, doi: 10.54287/gujsa.1832327.

ISNAD

Karabey, Onur Hamza. “A Novel Liquid Crystal Phase Shifter Enhanced Butler Matrix Topology for Continuously Steerable 60 GHz Antenna Array”. Gazi University Journal of Science Part A: Engineering and Innovation 13/1 (March 1, 2026): 215-228. https://doi.org/10.54287/gujsa.1832327.

JAMA

1.Karabey OH. A Novel Liquid Crystal Phase Shifter Enhanced Butler Matrix Topology for Continuously Steerable 60 GHz Antenna Array. GU J Sci, Part A. 2026;13:215–228.

MLA

Karabey, Onur Hamza. “A Novel Liquid Crystal Phase Shifter Enhanced Butler Matrix Topology for Continuously Steerable 60 GHz Antenna Array”. Gazi University Journal of Science Part A: Engineering and Innovation, vol. 13, no. 1, Mar. 2026, pp. 215-28, doi:10.54287/gujsa.1832327.

Vancouver

1.Onur Hamza Karabey. A Novel Liquid Crystal Phase Shifter Enhanced Butler Matrix Topology for Continuously Steerable 60 GHz Antenna Array. GU J Sci, Part A. 2026 Mar. 1;13(1):215-28. doi:10.54287/gujsa.1832327