Emran Md Amin

Development of a Low Cost Printable Chipless RFID Humidity Sensor

A novel low-cost chipless radio frequency identification tag sensor is presented. The tag sensor provides identification data as well as monitors relative humidity (RH) of tagged objects. The tag sensor is made of passive microwave circuit that uses humidity sensitive polymer material for RH sensing. The aim of this paper is to investigate RF sensing properties of moisture absorbing polymer polyvinyl alcohol at microwave frequency. In addition, frequency shifting technique is used to encode data bits for high data capacity. The overall size of the proposed tag sensor is 15 mm × 6.8 mm and has 6 bit data capacity for ID generation and single bit for humidity sensing. Results presented here show ~ 607 MHz frequency deviation for 50% RH increase. The tag sensor has potential to be printed on flexible laminates such as plastic and paper for ultra-low cost item level tagging and ubiquitous sensing.

Smart Sensing Materials for Low-Cost Chipless RFID Sensor

Smart materials for chipless RFID sensors have not been developed for the broadband/high speed wireless data communication yet. Their applications are confined to some dc and very high frequency physical sensors. In this paper, various smart materials for RF sensing applications and their characteristics in the influence of various physical parameters have been analyzed. The working principle of chipless RFID sensors along with their various design and experimental results as well as their potential application is also presented. This paper provides a pathway to low cost, passive, fully printable sensor nodes for realtime condition monitoring.

Development of a low cost printable humidity sensor for chipless RFID technology

In this paper, a low cost, printable chipless RFID humidity sensor is presented. The RFID sensor is based on planar stepped impedance resonator (SIR) structure. Humidity sensing mechanism is incorporated using dielectric change of commercially available Kapton HN polyamide. A prototype sensor is designed, fabricated and tested with standard experimental measurements. Results verify that the humidity sensitivity can be measured for both frequency and minimum power level difference. The proposed chipless RFID sensor platform has potential of integrating multiple sensing parameters for ubiquitous environment monitoring.

Development of a chipless RFID temperature sensor using cascaded spiral resonators

In this paper a fully printable low cost chipless RFID temperature sensor is presented. The chipless RFID comprises of multiresonator spirals coupled with a microstrip line. Each spiral represents a single data bit and the number of cascaded spirals corresponds to the number of bits it can store. The integration of temperature sensing is performed by utilizing the resonant frequency of a specific spiral of the tag. Unlike earlier reported works on chipless RFID temperature sensor our proposed sensor does not require any external circuitry or semiconductor chip for sensing environment temperature. Rather, it performs real time temperature sensing using the dielectric property of temperature dependent high K polyamides. Introducing high K dielectric material changes the equivalent capacitance of the LC resonator which varies with environment temperature. Results verify that a dedicated resonator can perform the sensing whereas the other cascaded resonators resemble the ID of the tag.

A novel EM barcode for humidity sensing

In this paper, a novel low cost, compact, printable EM barcode or chipless RFID tag is presented for humidity sensing. The RFID tag sensor is based on planar, single sided resonant scatters operating within the frequency band of 6.5 GHz to 9.5 GHz. Within this frequency range a rectangular patch with a number of slot resonators is designed to designate the data ID. In addition, an electric inductive-capacitive (ELC) resonator is dedicated for humidity sensing. The ELC resonator is modified using polyvinyl- alcohol (PVA) to incorporate humidity sensing. Moreover, the tag sensor can be printed on flexible laminates like plastic and paper for ultra-low cost item level tagging and ubiquitous sensing. The sensor tag has potential of including multiple parameter sensing as the sensing mechanism is independent of data ID generation. It has remarkable application in low cost perishable product process and management.

Towards low-cost, wireless blood anomaly sensing: An RFID-based anemia detection sensor

Paper based diagnostic devices have great potential in the low-cost sensing of blood diseases. However, patient blood testing using these devices is limited by tedious manual intervention and qualitative colorimetric readouts. We present the novel design of an RFID-based anemia detection sensor that integrates a paper-based diagnostic device with a passive Ultra High Frequency (UHF) RFID tag. Differences in red blood cell (RBC) count in a patients blood manifests itself as a controlled time-dependent change in the tags signal response. We demonstrate that our sensor is capable of reliably differentiating between blood having 20, 30, 40 and 50% RBC concentration by volume - indicative of anemic vs. healthy blood. Furthermore the sensor can be read using off the shelf RFID equipment allowing for automated screening of blood specimens at large scale. Challenges in sensor design and future research directions are also discussed.

Chipless RFID tag for light sensing

A fully passive chipless RFID tag with light sensing capabilities is presented for low-cost, maintenance-free applications. This paper describes the steps towards developing a prototype of passive light sensor using off the shelf photoresistors. Results show a single microwave resonator has 60 MHz frequency shift and 7.5 dB power variation for 0 to 1000 lux light intensity change. Future research direction and recommendations are also discussed.

A Passive RF Sensor for Detecting Simultaneous Partial Discharge Signals Using Time–Frequency Analysis

In this paper, a passive radio-frequency (RF) sensor has been presented for non-invasive radiometric detection of simultaneous partial discharge (PD) signals in high-voltage (HV) equipment. The sensor is a multi-resonator-based passive circuit with an antenna for capturing PD signals. The low-cost RF sensors are installed in HV sensing units for monitoring multiple units simultaneously. Each sensor captures PD signal and processes it with distinct spectral signatures as identification data bits and transmits the signal to a single sampling channel. From the captured RF signal, both the PD level and the source identification can be retrieved. Our proposed passive sensor addresses both aspects of PD monitoring, PD detection, and faulty source identification. Moreover, in identifying the data bits, the time-frequency analysis is utilized for superior detectability. This analysis enables the detection of multiple PD events separated by a defined time delay, although they occur at the same instance. Thus, the sensor can distinguish simultaneous PD occurrences from multiple sources, which is a novel contribution in PD detection. The proposed sensor system provides low-cost, passive condition monitoring of HV units in a distribution substation.

Passive RFID sensor for remote detection of Partial Discharge

A novel approach for non-invasive radiometric Partial Discharge (PD) detection and localization of faulty power apparatuses in switchyards using Radio Frequency Identification (RFID) based sensor is presented. The sensor is a multi-resonator based passive circuit with two antennas for reception of PD signal from the source and transmission of the captured PD to the base station. The sensor captures PD signal processes it with designated spectral signatures as identification data bits and retransmits the data with PD signals to the base station. Analyzing the PD signal in the base station, both the PD levels and source identifications can be retrieved. The prototype sensor was designed, fabricated, and tested for performance analysis. Results verify that the sensor is capable of identifying different sources at the events of PD.

Towards low-cost resolution optimized passive UHF RFID light sensing

This paper presents a low-cost, fully passive UHF RFID light sensor. We demonstrate how our design makes use of off-the-shelf photoresistors and LC components to establish a power frequency dependence which is used for improved sensor precision. Preliminary results show we can successfully identify 4 light intensity states between 0 to 1000 lux.