proximity coupling device (chipcard terminal) (PCD)

A Proximity Coupling Device(PCD) is a card reader for Proximity Integrated Circuit Cards( PICC), i.e. an RFID reader. The coupling between the PCD reader and the PICC cards is inductive and limited to small distances of up to 10 cm.

Wireless transmission is achieved by an alternating magnetic field induced in the flat antenna of the PICC card. Power is transferred from the PCD reader to the Vicinity Integrated Circuit Card( VICC) via the non-contact interface, as it is passive and has no battery. The data from the PICC card is interrogated by the PCD reader/writer and communication is bidirectional. PCD terminals operate with near field communication mostly on the frequency of 13.56 MHz.

The communication between the PCD reader unit and the PICC card is described in the ISO 14443 standard. The downlink from the PCD unit and the PICC card uses amplitude shift ke ying( ASK) in type A, and load modulation in the uplink. Type B uses Non Return to Zero( NRZ) instead of Manchester coding.