Development of low-cost backscattered semi-active RFID tag at 2.4 GHz

The development of a low-cost backscattered semi-active Radio Frequency Identification (RFID) tag that works in 2.4 GHz frequency band is presented in this study. The tag comprises of an annular ring slot antenna, a feed with a matching network, a Schottky diode modulator and a microcontroller with an in-built oscillator. The tag is powered by a 3 V pill-box battery and uses amplitude shift keying (ASK) modulation to communicate its identity to the tag reader. Results presented include the performance of the slot antenna, the feed network, the associated software and identification of the tag in real time by a Hyper-XR reader. ©2007 Wiley Periodicals, Inc.