IMPROVED CARD READER DEVICE FOR CONTACTLESS READABLE CARDS AND METHOD FOR OPERATING SAID CARD READER DEVICE

摘要

A card reader device is configured to carry out communication with a contactless readable card according to standard ISO/IEC 14443 type B. In order to provide that a modulation index, which self-adjusts in close range in a presence of a contactless readable card, corresponds to a desired specified modulation index, the magnetic field is received and evaluated via a reception antenna of the card reader device. The modulation index is controlled or regulated accordingly in case of deviations between a measured modulation index and a specified value for the modulation index in order to approximate the measured modulation index to the specified value.