An Introduction to UHF RFID

The latest standardization of the Ultra-High Frequency RFID spectrum is the GS1 UHF Gen2 protocol (ISO/IEC 18000-63), which defines the technical specifications (e.g., physical/logical interactions between devices, anti-collision algorithms, security commands, etc.) for RFID devices operating in the frequency of 860–860 MHz.

The ITU designated UHF (Ultra-High Frequency) as the radio frequency range of 300 MHz to 3 GHz, while the IEEE defines UHF as only frequencies between 300 MHz and 1 GHz (the rest of the ITU–defined UHF frequency range overlaps with the IEEE’s frequency allocations for the L band and the S band). The UHF spectrum is utilized by many organizations and industries worldwide. The UHF frequency range is allocated to specific purposes and entities, usually varying between countries. For example, in the United States, 420–450 MHz is used for amateur radio, 806–816 MHz is used for public safety and commercial 2-way channels, and 2290–2300 MHz is used by the NASA Deep Space Network (IEEE L band).

Unique UHF Characteristics

Long read ranges. Due to the nature of the UHF spectrum, UHF communication systems can reach much longer ranges than HF systems (NFC).

Low cost. UHF tags are relatively easy to manufacture and the components are not as expensive as the components used to manufacture HF tags. This is partially due to the relatively short antenna length necessary for UHF tags and readers.

Minimal risk of counterfeit tags. Because the process of duplicating UHF tag data is difficult, the risk of counterfeit tags (due to unauthorized duplication) is low.

Re-usable. The majority of UHF tags are reusable, meaning that they can be written and re-written to.