A Method to Determine The Structure Mode and Antenna Mode of A RFID Tag Antenna Scattering

摘要

The operation principle of a passive RFID is based on the modulated backscattering of the tag antenna which is alternatively connected to two different impedance loading states. In reality, the backscattered field of a tag antenna can be decomposed into two components: one is independent of the loading impedance, called the structure mode, and the other is dependent on the loading impedance, which is the only component we desire and is called the antenna mode [1]. In real environment, not only the field backscattered from the tag antenna, but also clutter field reflected from environments will be received. In this paper we will propose a method to determine the structure mode and antenna mode from the backscattering measurements.