Polarization-insensitive planar patch antenna with large embedded serial capacitance for on-metal tag design

Area of Science:

• Electrical Engineering
• Antenna Theory
• Radio-Frequency Engineering

Background:

• Metal mountable tags require robust antenna designs for reliable communication.
• Existing antennas often struggle with polarization sensitivity and performance degradation on metallic surfaces.

Purpose of the Study:

• To propose a polarization-insensitive planar patch antenna for metal mountable tags.
• To achieve omnidirectional readability and reduce resonant frequency using a single radiator.

Main Methods:

• Designing a planar patch antenna with closely overlapped flaps to create a large embedded serial capacitance.
• Analyzing surface currents and constructing an equivalent circuit to understand impedance properties.
• Investigating the antenna's performance on metallic surfaces and its insensitivity to backing materials.

Main Results:

• The proposed antenna exhibits polarization-insensitivity, enabling readability from almost all directions above a metal surface.
• A compact tag antenna was developed, achieving a read range of approximately 15m with 4W EIRP.
• The tag's resonant frequency showed minimal impact from the backing material.

Conclusions:

• The developed single-radiator planar patch antenna effectively overcomes polarization and metal-surface challenges for tag applications.
• This design offers a unique solution for robust and versatile metal mountable tags.
• The antenna's performance characteristics suggest significant advancements in RFID and sensor tag technology.