EPC Gen 2 RFID systems operate in the range of 860 MHz to 960 MHz, which is the frequency available for passive ultrahigh-frequency (UHF) RFID systems within most countries. There are tags designed to work across this range, while others are optimized for use within the United States, where tags operate between 902 MHz and 928 MHz (generally referred to as 915 MHz—the center point of the band).
If you were to use these tags within the United Kingdom, or in another European country in which 865 MHz to 868 MHz is used, you would be able to read the tag, but from a shorter distance. So the answer is yes, one system will work worldwide—but if you are tagging objects that will be read in Asia, Europe, North America and South America, you should choose a tag designed to function across a broad frequency range, rather than one optimized for a particular region.
—Mark Roberti, Founder and Editor, RFID Journal
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