A Highly Compact Antipodal Vivaldi Antenna Array for 5G Millimeter Wave Applications

Area of Science:

• Electromagnetics and Applied Electrophysics
• Antenna Theory and Design
• Wireless Communication Systems

Background:

• 5G millimeter-wave (mmWave) communication demands high-performance antennas for increased data rates.
• Existing antenna designs often face challenges with size, gain, and bandwidth for mmWave applications.
• Antipodal Vivaldi antennas (AVAs) offer potential for wide bandwidth but require optimization for compact form factors.

Purpose of the Study:

• To design and validate a compact 1x4 antipodal Vivaldi antenna (AVA) array for 5G mmWave frequency range 2 (FR2) bands.
• To enhance antenna performance in terms of gain, bandwidth, and front-to-back ratio while minimizing physical dimensions.
• To present a viable antenna solution for integration into compact 5G devices operating in FR2 bands.

Main Methods:

• A 1x4 antipodal Vivaldi antenna (AVA) array was designed using RT/Duroid 5880 substrate with integrated corrugations.
• Antenna size was minimized to 24 mm × 28.8 mm × 0.254 mm through optimized corrugations and substrate selection.
• Corporate feeding network was meticulously optimized to achieve enhanced bandwidth and narrow beamwidth, with performance validated through simulation and fabrication.

Main Results:

• The designed AVA array operates across two distinct frequency ranges: 24.19 GHz-29.15 GHz and 30.28 GHz-40.47 GHz.
• Achieved a high gain varying from 8 dBi to 13.2 dBi, with the maximum gain of 13.2 dBi observed at 40.3 GHz.
• Demonstrated significant size reduction and improved front-to-back ratio due to corrugations, leading to enhanced gain and stable radiation patterns across the operating frequencies.

Conclusions:

• The proposed compact AVA array offers substantial improvements in size, gain, and bandwidth compared to existing designs.
• The antenna covers key 5G FR2 bands (n257, n258, n260, n261), making it a strong candidate for 5G mmWave devices.
• Experimental validation confirmed the simulated performance, highlighting the antenna's practical applicability in millimeter-wave systems.