The type of reader you would require would depend on the distance at which you wanted to interrogate the bank card. You could use a passive high-frequency (HF) transponder, but the read distance would likely be only around 3 feet. You could utilize a passive ultrahigh-frequency (UHF) transponder, which would provide a longer read range (more than 25 feet, in many cases), but UHF radio waves are absorbed by water, of which the human body is mostly composed. That means it could be a challenge to read a tag within a wallet residing in a person’s pocket. Or you could employ active RFID transponders that would allow you to identify someone from more than 100 feet away.
Vail Resorts wanted to identify customers, but did not want to force skiers through a narrow HF portal, as is often done on European mountains. It chose to use UHF technology to identify skiers entering a chair lift, and to link each skier’s ID with a Web page that displays photos of that individual, along with the number of vertical feet he or she skied. The deployment has been very successful (see Vail Resorts Links RFID With Social Media).
And China Construction Bank is using active (battery-powered) RFID transponders in badges to identify VIP customers (see Chinese Banks Track Assets, Cash and VIP Customers). Each active tag broadcasts a signal, thereby ensuring that the tag is read and that the VIP customer is identified.
These solutions work in different scenarios, so I am unable to recommend a specific type of gate reader without knowing more about your particular application.
—Mark Roberti, Founder and Editor, RFID Journal
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