A Compact UHF RFID Tag for Metallic Objects

Opportunity

The introduction of this UHF RFID tag antenna, designed specifically for use on metal structures, addresses a significant need in automated factories and other industrial environments. The technology is available in two versions. The first version is a compact dual-band tag with folded strip structure, measuring only 20 mm × 30 mm × 1.5 mm. This tag can operate across different UHF bands, such as European and American frequencies, with unique reading patterns in each band. The second version is a single-band version, measuring just 10 mm × 30 mm × 1.5 mm, which is suitable for planar and conformal platforms, such as metallic cylinders and bearings. Automated factories can leverage these miniaturised tags with RFID technology to intelligently monitor machinery and equipment, ensuring operational efficiency and early detection of potential issues. 

Technology

The dual-band UHF RFID tag antenna’s main innovation lies in its compact size, making it the smallest among comparable tags. It measures 0.06 λ × 0.09 λ × 0.0045 λ, where λ is the wavelength of free space at 915 MHz. Unlike other products, this tag offers different reading patterns in two bands, ensuring a far identification distance (more than seven metres in European RFID band and more than five metres in the American RFID band) while maintaining high radiation efficiency. 

The single-band UHF RFID tag antenna also has a significantly reduced size, and measures only 0.03 λ × 0.09 λ × 0.0045 λ. This design ensures a far identification distance (more than five metres) with high radiation efficiency. 

Figure 1: Potential application of UHF RFID tag

Applications & Advantages

Main application areas include industrial intelligent RFID multifunctional detection systems; RFID positioning systems; RFID management for logistics, luggage, containers and shelves; as well as Internet-of-Things (IoT) sensors management.

Advantages: 

• Compact size and built on a flexible substrate.
• Compatible with existing RFID transceivers.
• High radiation efficiency.
• Different reading patterns for dual-band versions.
• Long identification distances despite small size.