Dual Polarization 2 × 2 Array Ku-Band Antenna with Improved Polarization Purity

Area of Science:

• Electromagnetics and Wave Propagation
• Antenna Theory and Design
• Microwave Engineering

Background:

• Dual-polarization antennas are crucial for modern wireless communication systems, offering increased spectral efficiency.
• Traditional dual-polarization feed networks often involve complex structures, increasing manufacturing costs and design challenges.
• Achieving high cross-polarization discrimination (XPD) is essential for reliable signal transmission in dual-polarized systems.

Purpose of the Study:

• To present a novel and simplified feed network for a Ku-band 2x2 patch array antenna.
• To enable independent vertical and horizontal polarization operation with a compact feed structure.
• To achieve superior cross-polarization performance and high gain across the operating bandwidth.

Main Methods:

• Design and simulation of a 2x2 patch array antenna utilizing a cooperative feed network.
• Implementation of a feed structure with two serially connected power dividers on a single plane.
• Utilizing microstrip lines for element placement and signal routing to enhance performance.
• Fabrication and measurement of the prototype antenna to validate simulation results.

Main Results:

• The proposed antenna supports dual-polarization (vertical and horizontal) through a simple feed network.
• Achieved a cross-polarization ratio better than 30 dB across the operating band.
• Demonstrated a realized gain greater than 10 dB for both polarization modes.
• The fabricated antenna operated at a center frequency of 14.9 GHz with a 6.8% fractional bandwidth.

Conclusions:

• The presented Ku-band patch array antenna with its cooperative feed network offers an effective solution for dual-polarization applications.
• The simplified feed structure reduces complexity and cost while maintaining high performance.
• Measurement results confirm the antenna's suitability for wireless communication systems requiring high isolation and gain.