Time-coded chipless RFID temperature sensor with self-calibration based on a Vivaldi antenna

Abstract

This paper proposes a radio frequency identification (RFID) sensor based on an ultra-wide band (UWB) Vivaldi antenna loaded with two transmission lines. The time-domain response is composed by a structural and two tag (or antenna) mode reflections. Each transmission line generates its own tag mode. One tag mode is used to sense temperature, and the other is used to calibrate the sensor. Experimental results obtained with two reader approaches are presented to validate the system.