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

摘要

The invention relates to a method for operating a card reader device (1) and to a card reader device (1). Said device is advantageously designed according to the invention to carry out communication with a contactless readable card according to the standard ISO/IEC 14443 type B. In order to provide that a modulation index that self-adjusts in the close range in the presence of a contactless readable card corresponds to a desired specified modulation index, the magnetic field is received and evaluated via a reception antenna (13) of the card reader device (1). The modulation index is controlled or regulated accordingly in case of deviations between the measured modulation index and the specified value for the modulation index in order to approximate the measured modulation index to the specified value.