High-frequency RFID tags: an analytical and numerical approach for determining the induced currents and scattered fields

RFID systems will soon become ubiquitous. This paper provides insight into one way of viewing the operation of high-frequency RFID systems that use passive tags. The relationship between the impedance of the tag circuit and the fields scattered by the tag are highlighted using two indepen- dent numerical codes. In addition, analytical expressions and numerical results for the scattered electric field are provided for a dipole with an assumed sinusoidal current distribution. Such results provide EMC engineers with an approximate method of determining the fields scattered from passive, high-frequency RFID tags.