Magazine Article | November 20, 2006

RFID Frequency Battle

Source: Field Technologies Magazine

RFID may eventually become a pervasive technology. But, it’s far from certain as to the frequency at which those smart labels will operate.

Integrated Solutions, December 2006

There’s little argument that RFID (radio frequency identification) is a technology that will be widely deployed over time. Reasonable people can certainly differ over the applications and the time frames to roll out this smart-label technology. But, the consensus is that RFID is an important technology that will have a dramatic impact on enterprises and individuals.

There is considerable debate, however, as to the frequency at which most RFID tags will operate in most applications. In particular, will passive UHF (ultra-high frequency) tags be pervasive? Or, will passive tags and applications employ both UHF and HF (high frequency)? This is hardly an inconsequential point. HF tags and applications have been in place for decades. The technology is accurate, mature, and widely understood. However, HF technology is comparatively more expensive than UHF, the form factors are larger than UHF, and read ranges are not nearly as great as UHF.

Until recently, these were all moot points. HF was a technology that could be used at the item level, while UHF could not be appropriately harnessed to work at the item level. Additionally, HF could be deployed with little regard for metal or liquid interference. This was the end of the story. Or, so it seemed. Advances in UHF technology have come so far in such a short time that some in the RFID industry are predicting that UHF will be a ubiquitous frequency. At best, HF will be used in niche applications. At worst, HF will become all but obsolete.


Whether UHF reaches the dominant position that some predict will largely be dependent on its development and adoption in the next 12 to 18 months. For example, UHF technology needs to be tested and retested by objective, third parties to determine its true accuracy in production environments. HF technology is already tested and proven to be accurate. Proponents of UHF claim the same level of accuracy, but don’t have the independent research to verify this claim. Additionally, UHF technology – under some very extreme conditions – can possibly alter biologicals being tagged. It’s up to the UHF community to either refute these assertions or prove that this occurrence is so rare that it’s a practical impossibility.

Determining the dominant RFID frequency, or whether several frequencies will be pervasive, is of critical importance to the industry and how it moves forward. If UHF is indeed the frequency of choice at the item level, this will have a dramatic impact on the pharmaceutical industry and how it complies with FDA and state regulations and policies. It will also have an impact on how other industries move forward with RFID deployments. For instance, retail supply chains are currently using UHF for case- and pallet-level shipments. In the future, UHF could be used on items and tracked on store shelves.

Of course, all of this “one frequency” ubiquity remains to be seen. HF is stable and mature. HF is accurate and understood. And, maybe most importantly, HF is deployed in applications where there are real returns and business cases. This is not to say that advancements in UHF could not offset all of the advantages of HF technology. But, until that happens, expect to see two frequencies sharing the RFID spotlight.