Measurement of localized specific absorption rate (SAR) for contactless smartcard readers operating in the HF band

This paper explores highly sensitive localized SAR measurement methods for contactless smartcard readers operating in the HF band, specifically 13.56 MHz. The design and calibration of a low-frequency E-field probe is described. A method for synthesizing simulated human tissue using a technique developed for measurement of the conductivity of liquids at the HF band is also presented. Finally, both the near-field and localized specific absorption rates are measured for a contactless smartcard reader and compliance with Federal Communications Commission (FCC) maximum permissible exposure (MPE) and specific absorption rate (SAR) regulation is determined.