Eur. Phys. J. Appl. Phys. (2016) 74: 24606
https://doi.org/10.1051/epjap/2015150376

Regular Article

A batteryless temperature sensor based on high temperature sensitive material^*

¹ Laboratory of Innovative Technologies, Abdelmalek Essaadi University, 1818 Tangier, Morocco
² Research Institute for Integrated Management of Coastal Areas, Universitat Politècnica, 46730 Valencia, Spain
³ Polydisplinary Faculty, Hassan 1st University, 25000 Khouribga, Morocco

^a e-mail: asma.bakkali@yahoo.fr

Received: 22 July 2015
Revised: 9 November 2015
Accepted: 12 November 2015
Published online: 3 May 2016

Abstract

The major challenge in wireless sensor networks is the reduction of energy consumption. Passive wireless sensor network is an attractive solution for measuring physical parameters in harsh environment for large range of applications requiring sensing devices with low cost of fabrication, small size and long term measurement stability. Batteryless temperature sensing techniques are an active research field. The approach developed in our work holds a promising future for temperature sensor applications in order to successfully reduce the energy consumption. The temperature sensor presented in this paper is based on the electromagnetic transduction principle using the integration of the high temperature sensitive material into a passive structure. Variation in temperature makes the dielectric constant of this material changing, and such modification induces variation in the resonant frequencies of high-Q whispering-gallery modes (WGM) in the millimeter-wave frequency range. Following the results achieved, the proposed device shows a linear response to the increasing temperature and these variations can be remotely detected from a radar interrogation.