A Passive Computational UHF RFID Platform Using Vector Backscatter Modulation

This article presents the design and implementation of a passive, computational ultra high frequency (UHF) radio frequency identification (RFID) platform using vector backscatter modulation on the uplink (tag-to-reader). The proposed RFID system consists of a software defined radio (SDR) reader and the corresponding passive, computational tag. The communication protocol is firmware-implemented, thus offering high flexibility in configuring its functionalities. A dual-gate MOSFET is used to implement the vector backscatter modulator. Experimental results prove the platform's feasibility and show the benefits of using vector backscatter communication compared to using the standard binary phase-shift keying (BPSK). For the investigated 128-bit tag-to-reader message based on the EPC Class 1 Generation 2 communication protocol, the sequence length was shortened by a factor of 1.91.