EMERGENT · ChiplEss MultisEnsor Rfid for GrEen NeTworks

ChiplEss MultisEnsor Rfid for GrEen NeTworks

EMERGENT project aimed to realize a new class of chipless Radio Frequency IDentification (RFID) tags and sensors moving from conventional wired-based sensors towards next generation pervasive Radio Frequency interconnected systems. Environmental-friendly substrates such as paper has been considered as well as low-cost fabrication processes. The technologies developed under EMERGENT project have the potential to foster the development of applications that can benefit from low-cost sensors and therefore it can represent an enabling technology for security, home automation and health. In conclusion, the project has demonstrated the operation capabilities in relevant evnvironment of three sensors. Two of them are based on chipless RFID sensors and the last one based on semi-passive RFID sensor. More in detail: 1) Temperature sensor: a chipless temperature threshold sensor structure in a real environment has been demonstrated. Two structures based on a C-scatterer designed to resonate in regulated frequency bands have been proposed. The proposed solution favours the implementation of an RFID chipless sensor in the real-world environment since it increases its compatibility with the commercially available conventional RFID readers. 2) Permittivity sensor: a permittivity sensing prototype based on depolarizing tags using dedicated reader has been reported. The sensor tag senses the permittivity of the material attached on its back side. A portable reader architecture for frequency-domain chipless tags operating in the range 1.9-2.5 GHz has been developed. The reader cost is roughly 120 dollars for 1Kpcs. The operation of the reader measuring depolarizing tags is demonstrated in non-anechoic environment at a distance of 20 cm. The fabricated reader has been tested with a 4-bit depolarizing tag in a multipath scenario. 3) Apnoea detector: a wireless apnoea detector using a semi-passive RFID tag has been presented. The device is based on the measurement of the airflow temperature changes that are produced during breathing. The wireless communication is performed by modulating the response of varactor-loaded frequency selective surfaces. This backscattering technique saves a lot of energy in comparison to its alternatives and guarantees a long lifetime for the device. A custom reader with IoT connection has also been developed using commercial components. Read ranges up to 3 m are typically obtained. A real time algorithm is used to measure the breathing rate and detect the apnoea intervals. Connection to the cloud is also demonstrated.

Data: CORDIS, © European Union