Physical-Layer Identification of HF RFID Cards Based on RF Fingerprinting

High frequency radio frequency identification (RFID) cards have been widely used in many fields. At the same time, a variety of security issues such as illegal cloning attacks have also arisen. Many security protocols have been proposed. However, most of them focused on security implication of the logical layer, little attention was paid to the physical-layer characteristics of cards. In this work, by investigating electromagnetic characteristics of HF RFID cards, a new method of extracting RF fingerprint is proposed based on higher order statistical features of ATQA envelope. By evaluating our technique on a set of 300 HF cards from 6 manufacturers, we can achieve accuracy of 100 % for all types. The influence of the placement on the fingerprint of the same card is also discussed. As the feature extraction can be implemented under normal working state of cards, it is practical to realize real-time identification of HF RFID cards.