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Passive frequency doubling antenna sensor for wireless strain sensing

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Details

Original languageEnglish
Title of host publicationASME 2012 Conference on Smart Materials, Adaptive Structures and Intelligent Systems, SMASIS 2012
Pages625-632
Number of pages8
Volume1
DOIs
Publication statusPublished - 2012
Publication typeA4 Article in a conference publication
EventASME 2012 Conference on Smart Materials, Adaptive Structures and Intelligent Systems, SMASIS 2012 - Stone Mountain, GA, United States
Duration: 19 Sep 201221 Sep 2012

Conference

ConferenceASME 2012 Conference on Smart Materials, Adaptive Structures and Intelligent Systems, SMASIS 2012
CountryUnited States
CityStone Mountain, GA
Period19/09/1221/09/12

Abstract

This paper presents the design, simulation, and preliminary measurement of a passive (battery-free) frequency doubling antenna sensor for strain sensing. Illuminated by a wireless reader, the sensor consists of three components, i.e. a receiving antenna with resonance frequency f0, a transmitting antenna with resonance frequency 2f0, and a matching network between the receiving and transmitting antennas. A Schottky diode is integrated in the matching network. Exploiting nonlinear circuit behavior of the diode, the matching network is able to generate output signal at doubled frequency of the reader interrogation signal. The output signal is then backscattered to the reader through the sensor-side transmitting antenna. Because the backscattered signal has a doubled frequency, it is easily distinguished by the reader from environmental reflections of original interrogation signal. When one of the sensor-side antennas, say receiving antenna, is bonded to a structure that experiences strain/deformation, resonance frequency of the antenna shifts accordingly. Through wireless interrogation, this resonance frequency shift can be measured by the reader and used to derive strain in the structure. Since operation power of the diode is harvested from the reader interrogation signal, no other power source is needed by the sensor. This means the frequency doubling antenna sensor is wireless and passive. Based on simulation results, strain sensitivity of this novel frequency doubling antenna sensor is around -3.84 kHz/με.