13.56-MHz Inductively Coupled Card Compatibility to Conducting Surfaces

The drive toward multiple-application SmartCards eliminates the need for multiple cards but requires that multiple programming and reading processes be accomplished with high performance and low cost. 13.56-MHz inductively coupled cards require reading and writing environments that are free of interference from electromagnetic sources, and of self-induced interference from conductive surfaces. Both parallel and non-parallel conductive surfaces are found to detune the card and affect the coupling. The 13.56-MHz inductively coupled card compatibility to the conductive surfaces illustrates a need to factor in all of the processing environmental factors during design.