Skip to main content

Chipless Liquid Sensing Using a Slotted Cylindrical Resonator

Cole, Alex J., Young, Paul R. (2017) Chipless Liquid Sensing Using a Slotted Cylindrical Resonator. IEEE Sensors Journal, 18 (1). pp. 149-156. ISSN 1530-437X. (doi:10.1109/JSEN.2017.2773023) (KAR id:65225)


A method for the wireless sensing of the permittivity and level of liquids is presented. The use of a simple, thin-film slotted cylindrical cavity wrapped around a standard polytetrafluoroethylene pipe is proposed. Wireless interrogation of the slot excites a resonant mode whose frequency is dependent on the liquid currently present within the pipe. The proposed method allows for measurements to be taken in situ with no requirement for taking samples of potentially hazardous liquids. The device is capable of sensing materials of high relative permittivity, including water, as well as very lossy liquids. A comprehensive set of results is presented, including measurements of butanol, ethanol, methanol and water, for several device configurations. The proposed sensor is also shown to be sensitive to small changes in liquid level, allowing for accurate water level measurements down to 0:1 ml. This sensor is a good candidate for very low-cost, low-complexity real-time monitoring of liquids.

Item Type: Article
DOI/Identification number: 10.1109/JSEN.2017.2773023
Uncontrolled keywords: microwave sensors; microwave measurements; resonant frequency; chipless; liquids; level measurement.
Subjects: Q Science
Divisions: Divisions > Division of Computing, Engineering and Mathematical Sciences > School of Engineering and Digital Arts
Depositing User: Paul Young
Date Deposited: 11 Dec 2017 15:30 UTC
Last Modified: 09 Dec 2022 06:34 UTC
Resource URI: (The current URI for this page, for reference purposes)

University of Kent Author Information

Cole, Alex J..

Creator's ORCID:
CReDIT Contributor Roles:

Young, Paul R..

Creator's ORCID:
CReDIT Contributor Roles:
  • Depositors only (login required):

Total unique views for this document in KAR since July 2020. For more details click on the image.