Thermal Modeling of Resonant Scatterers and Reflectometry Approach for Remote Temperature Sensing

Chipless labels detection by backscattering for identification and sensing applications

“…In practical terms, it is now expected to show that it is possible to associate the chipless label ID with other features like the ability to: (1) write and rewrite the information (ID) [26], (2) associate an ID with a sensor function [27,28], (3) associate an ID with gesture recognition [29,30]. As compared to the barcodes, the chipless technology must bring other features that are impossible to implement with the optical approach, while remaining a very low-cost approach, that is to say, a printable one.…”

“…Thus, based on this principle, it is possible to carry out very precise measurements, remotely, such as the characterisation of the dilation coefficients of metals [12]. If, on the other hand, the temperature dependence of the materials that make up the tag is considered to be known, it is possible to use it as a temperature sensor [27,37]. Results on tags with no specific material (i.e.…”

“…Thus, it is possible to trace the value of the physical quantity through the measurement of this backscattered field, most often through the value of the resonance frequency. The correspondence between the resonance frequency and the value of the physical quantity is usually done using a lookup table or, when the problem is simple enough, by a direct analytical model [27,37]. Figure 8c, d show measurements made on resonators where drops of silicon nanowire have been deposited [28].…”

Combined Temperature and Humidity Chipless RFID Sensor

“…These frequency shifts are used to compute the ambient humidity around the resonator. At the same time, multiple chipless RFID temperature sensors have been made [15]- [18] based on the same idea, i.e. temperature variations induce…”

“…Similar phenomena is observed for humidity. One of the advantages highlighted with this remote reading approach is the possibility to retrieve the tag identifiant (ID) along with the temperature even through some everyday objects, such as through a wall or a door [18]. A summary of recent works is presented in Table I.…”