Compact Modified Quatrefoil-Shaped Antenna with Dual-Circularly Polarized 28/38 GHz for 5G and Beyond Millimeter-Wave...

Area of Science:

• Electrical Engineering
• Electromagnetics and RF Engineering
• Wireless Communications

Background:

• Emerging 5G and beyond wireless systems require efficient antennas operating at millimeter-wave frequencies.
• Compact and high-performance antennas are crucial for integrating millimeter-wave technology into space-constrained devices.
• Circular polarization (CP) is desirable for mitigating multipath fading and polarization mismatch in wireless links.

Purpose of the Study:

• To design and validate a compact, dual-band, circularly polarized antenna for millimeter-wave applications.
• To achieve efficient radiation and robust CP performance at 28 GHz and 38 GHz.
• To demonstrate the suitability of the antenna for 5G and future high-frequency wireless systems.

Main Methods:

• Design of a single-element antenna with an ultra-small radiating patch (3.34 mm × 3.34 mm) on a Rogers RO3003 substrate.
• Analysis of surface current distribution to confirm CP generation at 28 GHz and 38 GHz.
• Measurement of antenna performance, including axial ratio, radiation efficiency, gain, impedance matching, and radiation patterns.

Main Results:

• Successful achievement of circular polarization with axial ratios of 1.4 dB (28 GHz) and 2.2 dB (38 GHz).
• High radiation efficiency of ~87% at 28 GHz and ~82% at 38 GHz.
• Peak realized gains of 7.5 dBi (28 GHz) and 5.5 dBi (38 GHz) with excellent impedance matching and stable radiation patterns.

Conclusions:

• The proposed antenna offers a compelling combination of compact size, dual-band CP operation, and high efficiency.
• It is a promising candidate for millimeter-wave front-end integration in 5G base stations, user equipment, and future wireless platforms.
• The design validates the feasibility of achieving robust CP performance in miniaturized millimeter-wave antennas.