Study and development of techniques, circuits and applications for contactless interrogation of coil-coupled passive sensors

Contactless sensing of chemical and physical quantities is an attractive option for applications where wired connections are difficult to adopt or not possible. Such situations include measurements in enclosed/hermetic/hostile and/or high-temperature/harsh environments, measurements in moving systems, or the readout of implantable sensors. In this scenario, my research activity deals with the study and development of techniques, circuits and applications for contactless interrogation of passive coil-coupled sensors, i.e. devices which do not require batteries, active components and integrated circuits to operate. Specifically, the development of passive sensor units having a resonant behavior that allows to extract the measurement information through the contactless readout of the resonant frequency will be considered. This approach has the advantage of being robust and unaffected by the disturbances, such as noise and electromagnetic interferences, which typically affect the signal amplitude. To this extent, the development of techniques that have a specific controlled dependency on the coupling between the coils is essential for the successful implementation of the contactless readout. The proposed techniques offer the promising advantage of reducing the cost of the passive sensor unit, allowing the production of sustainable and/or disposable sensor units, such as labels or patches embedding one more passive sensors.