The transponders and readers used in passports operate in the high-frequency (HF) range and are based on the ISO 14443 standard. This standard is for short-range transmission of data, which is referred to as the standard for proximity cards.
These tags do not comply with EPCglobal‘s ultrahigh-frequency (UHF) standard. UHF is a longer-range technology and is unsuitable for this application, because one does not want everyone within 20 feet to be able to read the transponder in one’s passport.
It should be pointed out that many writers and bloggers often confuse the use of EPC transponders in PASS cards and ISO 14443 transponders in passports. One is meant to be read at short range, the other at longer range.
With a passport, an immigration official opens the document and reads its tag at short range. With the PASS card, part of the Western Hemisphere Travel Initiative, the longer-range UHF tags are used so that the tag can be read as a car approaches an immigration checkpoint. By the time the car pulls up, data about the PASS card holder can be accessed from the database.
—Mark Roberti, Editor, RFID Journal
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