Proximity Cards

Smart cards with contacts have to be inserted into readers before use, which is inconvenient in some applications. Proximity cards, otherwise known as contactless smart cards, dispense with the contacts and instead use radio frequency transmit/receive electronics to transfer the data.

Proximity cards are somewhat more complex in that they contain a large antenna in addition to the chip, and the power supply for the chip is now supplied via the RF energy from the reading device.

There are several relevant ISO standards including ISO 14443 A&B and ISO 15693, but in addition, individual vendors have defined their own proprietary encoding schemes such as Mifare, Legic and I-class.

All of these cards operate at 13.56 MHz, and claimed read ranges vary from 10 cm up to 1 metre depending on the modulation and data rate used. There is currently a lower limit on emitted power in the USA (FCC) than in Europe and the rest of the world (ISO), and this can restrict read ranges to as little as a few centimeters in some situations.

The extra chip "overhead" involved in the communications link and the power generation functions, plus the restriction of the maximum data transmission rate attainable, limits the functionality and data storage capacity of Contactless-cards to less than that available with contact cards. Even so, the convenience of use is greatly improved, and it is tempting to assume that in the near future, all smart cards will use this approach.

The Magicard Rio and Tango can both be fitted with Contactless Smart card encoders which allow cards to be initialized and pre-loaded pRior to printing.