To answer your question, I reached out to Steve Halliday, a principal at High Tech Aid, a leading consulting company focused on automatic identification and data capture (AIDC) technologies. Here is his response:
“A combo tag that uses both UHF [ultrahigh-frequency] and LF [low-frequency] is a fairly standard process for many of the active tag suppliers. Typically, the LF is used to wake up the tag and tell it to communicate. There are no specific regulations that govern this type of system. The tag and reader must conform to the regulations for the two frequencies used as if they are separate systems (which, in fact, they are).
“The UHF and LF bands are different in many parts of the world. LF ranges from 125 kHz to 134 kHz. UHF ranges from 860 MHz to 960 MHz. In many countries, 125 kHz and 868 MHz are not legal.
“The power levels for each country can be different as well, and you will need to search out the regulations for the country within which you are interested in using the system. This involves contacting the regulatory authorities for each country, and getting the necessary regulations. AIM Inc. used to offer access to a database that contained all of this information. I’m not sure if they still do.”
—Mark Roberti, Founder and Editor, RFID Journal
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