Humidity-Sensing Chipless RFID Tag with Enhanced Sensitivity Using an Interdigital Capacitor Structure

An eight-bit chipless radio frequency identification tag providing humidity sensing and identification information is proposed. A compact, enhanced-sensitivity resonator based on an interdigital capacitor (IDC) structure is designed for humidity sensing, whereas seven electric-field-coupled inductor capacitor (ELC) resonators are used for identification information. These eight resonators are placed in a two-by-four array arrangement. A step-by-step investigation for the effect of varying the number of elements and array configuration on the resonant frequency and radar cross-section (RCS) magnitude of the IDC resonator is conducted. The RCS value of the resonant peak frequency for the IDC resonator increases as the number of array elements placed nearby increases due to the mutual coupling among the elements, and the increase in the RCS value becomes larger as the number of arrays increases in the vertical direction. Polyvinyl alcohol (PVA) is coated on the IDC-based resonator at a thickness of 0.02 mm. A non-reflective temperature and humidity chamber is fabricated using Styrofoam, and the relative humidity (RH) is varied from 50% to 80% in 10% intervals at 25 °C in order to measure a bistatic RCS of the proposed tag. The humidity sensing performance of the IDC resonator in the proposed tag is measured by the shift in the resonant peak frequency and the RCS value, and is compared with a single ELC resonator. Experiment results show that when RH increased from 50% to 80%, the sensitivities of both the resonant peak frequency and the RCS value of the IDC resonator were better than those of the ELC resonator. The variation in the RCS value is much larger compared to the resonant peak frequency for both IDC and ELC resonators. In addition, the resonant peak frequency and RCS value of the PVA-coated IDC-based resonator change, whereas those of the other seven resonators without a PVA coating do not change.

[1]  Cristian Herrojo,et al.  Chipless-RFID: A Review and Recent Developments , 2019, Sensors.

[3]  Nemai Chandra Karmakar,et al.  Chipless RFID Sensors , 2016 .

[4]  Chi-En Lu,et al.  Humidity Sensors: A Review of Materials and Mechanisms , 2005 .

[5]  Prince M. Anandarajah,et al.  A Review of Chipless Remote Sensing Solutions Based on RFID Technology , 2019, Sensors.

[6]  Klaus Finkenzeller,et al.  Rfid Handbook: Fundamentals and Applications in Contactless Smart Cards and Identification , 2003 .

[7]  N. Karmakar,et al.  Development of a chipless RFID temperature sensor using cascaded spiral resonators , 2011, 2011 IEEE SENSORS Proceedings.

[8]  Filippo Costa,et al.  A Review of RFID Sensors, the New Frontier of Internet of Things , 2021, Sensors.

[9]  Qing‐An Huang,et al.  Simultaneous Remote Sensing of Temperature and Humidity by LC-Type Passive Wireless Sensors , 2015, Journal of Microelectromechanical Systems.

[10]  S. Tedjini,et al.  Chipless RFID Tag Using Hybrid Coding Technique , 2011, IEEE Transactions on Microwave Theory and Techniques.

[11]  Mohd Nizar Hamidon,et al.  Humidity Sensors Principle, Mechanism, and Fabrication Technologies: A Comprehensive Review , 2014, Sensors.

[12]  Etienne Perret,et al.  A compact chipless RFID tag with environment sensing capability , 2012, 2012 IEEE/MTT-S International Microwave Symposium Digest.

[13]  G. Manara,et al.  An Inkjet Printed Chipless RFID Sensor for Wireless Humidity Monitoring , 2017, IEEE Sensors Journal.

[14]  M. A. Belkerdid,et al.  Ultra wide band surface acoustic wave (SAW) RF ID tag and sensor , 2009, MILCOM 2009 - 2009 IEEE Military Communications Conference.

[15]  C. Di Natale,et al.  Polymer-doped UHF RFID tag for wireless-sensing of humidity , 2012, 2012 IEEE International Conference on RFID (RFID).

[16]  Nemai Karmakar,et al.  Chipless RFID tag with integrated sensor , 2010, 2010 IEEE Sensors.

[17]  G. Marrocco,et al.  A passive temperature radio-sensor for concrete maturation monitoring , 2014, 2014 IEEE RFID Technology and Applications Conference (RFID-TA).

[18]  S. Tedjini,et al.  A Group-Delay-Based Chipless RFID Humidity Tag Sensor Using Silicon Nanowires , 2013, IEEE Antennas and Wireless Propagation Letters.

[19]  Etienne Perret,et al.  Radio Frequency Identification and Sensors: From RFID to Chipless RFID , 2014 .

[20]  G. Marrocco,et al.  Passive RFID Strain-Sensor Based on Meander-Line Antennas , 2011, IEEE Transactions on Antennas and Propagation.

[21]  Manos M. Tentzeris,et al.  A Depolarizing Chipless RFID Tag with Humidity Sensing Capability , 2018, 2018 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting.

[22]  Etienne Perret,et al.  Toward a Reliable Chipless RFID Humidity Sensor Tag Based on Silicon Nanowires , 2016, IEEE Transactions on Microwave Theory and Techniques.

[23]  Nemai Karmakar,et al.  Chipped Versus Chipless RF Identification: A Comprehensive Review , 2019, IEEE Microwave Magazine.

[24]  N. Karmakar,et al.  Polyvinyl-alcohol (PVA)-based RF humidity sensor in microwave frequency , 2013 .

[25]  Holger Maune,et al.  Passive wireless temperature sensing with BST-based chipless transponder , 2011, 2011 German Microwave Conference.

[26]  Massimo Donelli,et al.  Chipless RFID Sensors for the Internet of Things: Challenges and Opportunities , 2020, Sensors.

[27]  Zhen Li,et al.  Radio Frequency Identification and Sensing Techniques and Their Applications—A Review of the State-of-the-Art , 2019, Sensors.

[28]  Lauri Sydanheimo,et al.  Temperature sensor tag for passive UHF RFID systems , 2011, 2011 IEEE Sensors Applications Symposium.

[29]  Tara Betts.  Humidity , 1912, Buffalo medical journal.