Analytical considerations for an ISO/IEC14443 compliant SmartCard transponder

We derive and use an analytical formula to describe some aspects in the RF behaviour of Smartcard transponders at the contactless air interface. The aspects we consider contain minimum operating H-field, thermal loading, card loading and maximum load modulation depending on transponder equivalent circuit parameters. We not only consider results, but also carefully discuss the approximations and simplifications we make, which should give an understanding of the principle and thereby allow for adaptations to selected fabrication technologies among the variety of existing options.