Tampere University of Technology

TUTCRIS Research Portal

Design and development of a novel passive wireless ultrasensitive RF temperature transducer for remote sensing

Research output: Contribution to journalArticleScientificpeer-review


Original languageEnglish
Article number6208808
Pages (from-to)2756-2766
Number of pages11
JournalIEEE Sensors Journal
Issue number9
Publication statusPublished - 2012
Publication typeA1 Journal article-refereed


A wireless, passive, and ultrasensitive temperature transducer is presented in this paper. The transducer consists of split ring resonators loaded with micro-bimorph cantilevers, which can potentially operate up to millimeter-wave frequencies (above 30 GHz). As the temperature changes, the bimorph cantilevers deflect and result in a shift of the resonant frequency of the split rings. A design is proposed, that has a maximum sensitivity of 2.62 GHz/μ m, in terms of frequency shift per deflection unit, corresponding to a sensitivity of 498 MHz/°C for an operating frequency around 30 GHz, i.e., a frequency shift of 1.6% per °C. Theoretically, it's about two orders of magnitude higher than the existing sensors observed in the same class. This sensor design also offers a high Q factor and is ultra-compact, enabling easy fabrication and integration in micro-electromechanical systems technology. Depending on the choice of materials, the proposed designs can also be utilized in harsh environments. As a proof of concept, a prototype is implemented around 4.7 GHz which exhibits a frequency shift of 0.05%/°C, i.e., 17 times more sensitive than the existing sensors.


  • Micro-electromechanical systems (MEMS) cantilevers, passive remote sensing, radar cross section (RCS), radio frequency transducer, split ring resonators (SRRs), temperature sensor, wireless sensor