Compact Multi Bit Slotted C-Scatterer for Threshold Sensitive Chipless Wireless Temperature Sensor

This paper presents a novel compact scatterer structure for a passive chipless wireless temperature threshold sensor. The structure is based on a single C-scatterer with multiple embedded slots; each slot forms a sub-scatterer dedicated to resonating in one regulated band. This structure has the advantage of increasing the data capacity without increasing the number of scatterers, which results in a more compact sensor size. The sensing principle is based on the detuning of the resonance frequency peaks of the backscattered signal from the slotted scatterer due to temperature variations. For the first time, this work demonstrates the design of a passive chipless sensor while at the same time respecting the conventional radio frequency (RF) emission regulations. The sensor only exploits the allowed bands: European Telecommunications Standards Institute (ETSI) and Industrial, Scientific and Medical (ISM). Sensitivity measurement results show sensitive characteristics in the order of 10−4 GHz/°C in accordance with the theoretical predictions.