{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T01:31:30Z","timestamp":1760232690736,"version":"build-2065373602"},"reference-count":27,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2022,11,18]],"date-time":"2022-11-18T00:00:00Z","timestamp":1668729600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Petroleum Technology Development Fund (PTDF), Abuja, Nigeria","award":["PTDF\/ED\/PHD\/MI\/888\/16"],"award-info":[{"award-number":["PTDF\/ED\/PHD\/MI\/888\/16"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>RF-based sensors are an attractive option for structural-health-monitoring applications, due to the ease of access of interrogating such sensors. However, in most work, only scalar quantities are measured, giving no indication of the direction of strain or displacements. In this paper, a novel approach to displacement sensing is presented, in which relative displacements are tracked in all three degrees of freedom. The sensor design is based on a pair of coupled line-element filters whose frequency-dependent forward-power transfer is sensitive to relative positions between the two filters. Multiple features in the S21 parameter are used to differentiate displacement direction. Gold-based devices were fabricated on quartz substrates, and characterised through vector-network-analyzer measurements. Results demonstrate uncoupled sensitivities of \u22121.41 MHz\/mm, \u22121.74 MHz\/mm and 12.23 MHz\/mm for x, y and z displacements, respectively.<\/jats:p>","DOI":"10.3390\/s22228908","type":"journal-article","created":{"date-parts":[[2022,11,18]],"date-time":"2022-11-18T06:11:34Z","timestamp":1668751894000},"page":"8908","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["RF Line-Element Filters for Structural-Health-Monitoring Applications"],"prefix":"10.3390","volume":"22","author":[{"given":"Idris","family":"Musa","sequence":"first","affiliation":[{"name":"School of Engineering, Newcastle University, Newcastle-upon-Tyne NE1 7RU, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2893-8776","authenticated-orcid":false,"given":"John","family":"Hedley","sequence":"additional","affiliation":[{"name":"School of Engineering, Newcastle University, Newcastle-upon-Tyne NE1 7RU, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"22","DOI":"10.1007\/s10921-018-0475-3","article-title":"A Novel RFID-Based Strain Sensor for Wireless Structural Health Monitoring","volume":"37","author":"Kuhn","year":"2018","journal-title":"J. Nondestruct. Eval."},{"key":"ref_2","first-page":"39","article-title":"Patch antenna sensor rosettes for surface strain measurement","volume":"170","author":"Dan","year":"2017","journal-title":"Proc. Inst. Civ. Eng., Smart infrastruct. constr."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"286","DOI":"10.1109\/JSEN.2016.2631259","article-title":"An RFID-Enabled Wireless Strain Gauge Sensor for Static and Dynamic Structural Monitoring","volume":"17","author":"DiGiampaolo","year":"2017","journal-title":"IEEE Sens. J."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"e2321","DOI":"10.1002\/stc.2321","article-title":"A literature review of next-generation smart sensing technology in structural health monitoring","volume":"26","author":"Sony","year":"2019","journal-title":"Struct Control Health Monit."},{"key":"ref_5","unstructured":"Lynch, J., Sohn, H., and Wang, M. (2022). Sensor Technologies for Civil Infrastructures Volume 1: Sensing Hardware and Data Collection Methods for Performance Assessment, Woodhead Publishing (Elsevier). [2nd ed.]."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1583","DOI":"10.1109\/JPROC.2010.2053690","article-title":"RFID: From Supply Chains to Sensor Nets","volume":"98","author":"Roy","year":"2010","journal-title":"Proc. IEEE"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.autcon.2015.02.013","article-title":"Rapid structural condition assessment using radio frequency identification (RFID) based wireless strain sensor","volume":"54","author":"Zhang","year":"2015","journal-title":"Autom. Constr."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"34","DOI":"10.1016\/j.sna.2016.02.010","article-title":"Low frequency (LF) RFID sensors and selective transient feature extraction for corrosion characterisation","volume":"241","author":"Sunny","year":"2016","journal-title":"Sens. Actuator A Phys."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"421","DOI":"10.1016\/j.measurement.2016.06.041","article-title":"Identification and characterisation of steel corrosion using passive high frequency RFID sensors","volume":"92","author":"Zhang","year":"2016","journal-title":"Measurement"},{"key":"ref_10","unstructured":"Saitoh, A., and Nomura, T. (2009, January 18\u201321). Wireless Sensor System Using Surface Acoustic Wave Devices. Proceedings of the ICROS-SICE International Joint Conference, Fukuoka International Congress Center, Fukuoka, Japan."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"5527","DOI":"10.1109\/JSEN.2015.2444812","article-title":"Wireless SAW Strain Sensor Using Orthogonal Frequency Coding","volume":"15","author":"Humphries","year":"2015","journal-title":"IEEE Sens. J."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"5725","DOI":"10.1109\/JSEN.2016.2567221","article-title":"Passive Wireless Frequency Doubling Antenna Sensor for Strain and Crack Sensing","volume":"16","author":"Cho","year":"2016","journal-title":"IEEE Sens. J."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"085009","DOI":"10.1088\/0964-1726\/22\/8\/085009","article-title":"Passive wireless antenna sensor for strain and crack sensing\u2014Electromagnetic modeling, simulation, and testing","volume":"22","author":"Yi","year":"2013","journal-title":"Smart Mater. Struct."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"6147","DOI":"10.1109\/JSEN.2015.2453947","article-title":"Sensitivity Modeling of an RFID-Based Strain Sensing Antenna with Dielectric Constant Change","volume":"15","author":"Yi","year":"2015","journal-title":"IEEE Sens. J."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"776","DOI":"10.1109\/JOE.2016.2572838","article-title":"Development of Wireless and Passive Corrosion Sensors for Material Degradation Monitoring in Coastal Zones and Immersed Environment","volume":"41","author":"Khalifeh","year":"2016","journal-title":"IEEE J. Ocean. Eng."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"4395","DOI":"10.1109\/JSEN.2014.2335743","article-title":"Stretchable RFID for Wireless Strain Sensing With Silver Nano Ink","volume":"14","author":"Kim","year":"2014","journal-title":"IEEE Sens. J."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"6412","DOI":"10.1109\/TAP.2014.2360553","article-title":"Wireless Crack Monitoring by Stationary Phase Measurements from Coupled RFID Tags","volume":"62","author":"Caizzone","year":"2014","journal-title":"IEEE Trans. Antennas Propag."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"197","DOI":"10.1016\/j.sna.2012.11.007","article-title":"Passive wireless displacement sensor based on RFID technology","volume":"190","author":"Cazeca","year":"2013","journal-title":"Sens. Actuator A Phys."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1244","DOI":"10.1109\/TCPMT.2015.2461661","article-title":"A Novel Enhanced-Performance Flexible RFID-Enabled Embroidered Wireless Integrated Module for Sensing Applications","volume":"5","author":"Hasani","year":"2015","journal-title":"IEEE Trans. Compon. Packag. Manuf. Technol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"32","DOI":"10.1108\/02602281111099062","article-title":"Embedded wireless strain sensors based on printed RFID tag","volume":"31","author":"Merilampi","year":"2011","journal-title":"Sens. Rev."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"814","DOI":"10.1109\/LAWP.2014.2318996","article-title":"Epidermal Passive RFID Strain Sensor for Assisted Technologies","volume":"13","author":"Rakibet","year":"2014","journal-title":"IEEE Antennas Wirel. Propag. Lett."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"015201","DOI":"10.1088\/0957-0233\/20\/1\/015201","article-title":"Exploiting a patch antenna for strain measurements","volume":"20","author":"Tata","year":"2009","journal-title":"Meas. Sci. Technol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"035201","DOI":"10.1088\/0957-0233\/21\/3\/035201","article-title":"Wireless interrogation of passive antenna sensors","volume":"21","author":"Deshmukh","year":"2010","journal-title":"Meas. Sci. Technol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"86","DOI":"10.1016\/j.sna.2012.07.003","article-title":"Wireless strain measurement using circular microstrip patch antennas","volume":"184","author":"Daliri","year":"2012","journal-title":"Sens. Actuator A Phys."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Zhang, J., Tian, G.Y., Marindra, A.M.J., Sunny, A.I., and Zhao, A.B. (2017). A Review of Passive RFID Tag Antenna-Based Sensors and Systems for Structural Health Monitoring Applications. Sensors, 17.","DOI":"10.3390\/s17020265"},{"key":"ref_26","first-page":"243","article-title":"Design, Simulation and Development of Filter in S band","volume":"2","author":"Vaghela","year":"2015","journal-title":"J. Emerg. Technol. Innov. Res."},{"key":"ref_27","unstructured":"Musa, I. (2022). A Microstrip based RF Filter for Biosensor Applications. [Ph.D. Thesis, Newcastle University]."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/22\/8908\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:20:47Z","timestamp":1760145647000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/22\/8908"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,11,18]]},"references-count":27,"journal-issue":{"issue":"22","published-online":{"date-parts":[[2022,11]]}},"alternative-id":["s22228908"],"URL":"https:\/\/doi.org\/10.3390\/s22228908","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2022,11,18]]}}}