Analysis and Design of a Long Range PTFE Substrate UHF RFID Tag for Cargo Container Identification

In this paper, a high-performances microstrip antenna for UHF (ultra high frequency) RFID (radio frequency identification) tag is designed, prototyped and tested. The antenna consists of two main components: a 1.52 mm RT/duroid 5880 laminate substrate on which the antenna is designed and a 10 mm polytetrafluoroethylene (PTFE) dielectric material placed as a separator between the antenna and the reference ground plane for the microstrip antenna. With this structure, the RFID tag can reach a maximum reading distance of 19 m, although the antenna has a compact size of 80 mm × 50 mm. The long reading distance is obtained by attaching to the antenna an RFID chip that can provide a reading sensitivity of −20.5 dBm. The high bandwidth from 677 MHz to 947 MHz measured at −10 dB, makes the tag being usable worldwide especially for cargo container identification, the main purpose of this research.