UHF RFID Conductive Fabric Tag Design Optimization

Area of Science:

• Electrical Engineering
• Materials Science
• Electromagnetics

Background:

• Radio Frequency Identification (RFID) technology is crucial for automated identification and tracking.
• Conductive fabrics offer potential for integrated and flexible RFID antennas.
• Designing efficient UHF RFID antennas from conductive fabrics presents unique challenges due to material properties.

Purpose of the Study:

• To design and evaluate a 920 MHz UHF RFID conductive fabric tag antenna.
• To investigate the impact of fabric conductivity on antenna performance.
• To compare the performance of two different-sized fabric tag antennas.

Main Methods:

• Measured DC resistance and impedance of conductive fabrics using a DC multimeter and network analyzer.
• Calculated fabric conductivities and utilized them in CST simulations for antenna design.
• Fabricated and simulated two T-Matching structure UHF RFID tag antennas (80x40 mm and 40x23 mm).
• Evaluated antenna performance through reflection coefficient (S11), radar cross-section, and reading range measurements.

Main Results:

• Simulated and measured antenna characteristics were compared.
• The 80x40 mm fabric tag antenna achieved a reading range of approximately 4 meters.
• The 40x23 mm fabric tag antenna achieved a reading range of approximately 0.5 meters.

Conclusions:

• Conductive fabric tag antennas can be effectively designed and fabricated for UHF RFID applications.
• Antenna size significantly influences the reading range, with larger antennas performing better.
• These fabric RFID tags are suitable for integration into textiles for systems like entrance control.