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Feature Papers in Electronic Sensors

A special issue of Sensors (ISSN 1424-8220). This special issue belongs to the section "Electronic Sensors".

Deadline for manuscript submissions: closed (31 December 2023) | Viewed by 21224

Special Issue Editors

Department of Electronics, Peking University, Beijing 100871, China
Interests: nanosensors; flexible integrated circuits; energy harvesting technology; integrated smart sensor systems
Special Issues, Collections and Topics in MDPI journals
Institut National de la Recherche Scientifique (INRS), Montréal, QC H2X 1E3, Canada
Interests: microwave and millimeter wave circuits and systems; six-port transceivers; high-speed wireless communications; radar and imaging sensors
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

We are pleased to announce that the Section Electronic Sensors is now compiling a collection of papers submitted by the Section Editorial Board Members (EBMs) as well as outstanding scholars in this research field. We welcome both contributions and recommendations from the EBMs.

The purpose of this Special Issue is to publish a set of papers that typify the very best insightful and influential original research articles or reviews where our Section’s EBMs discuss key topics in the field. We expect these papers to be widely read and highly influential within the field. All papers in this Special Issue will be collected into a printed edition book after the deadline, and will be well promoted.

We would also like to take this opportunity to call on more scholars to join the Section Electronic Sensors so that we can work together to further develop this exciting field of research. Potential topics include but are not limited to the following:

  • Electronic Sensors, Devices and Systems
    • Current/voltage/impedance sensors, magnetic sensors, acoustic sensors, image sensors, photodetectors, radars and radiometers, etc.
    • Microelectronic sensors, mechatronics, microelectromechanical, MEMS, piezoelectric, piezoresistive, triboelectric, optoelectronic, thermoelectric, CMOS sensors, etc.
    • Radiofrequency sensors, microchip, antennas, radio receiver and transmitter, PCB, etc.
  • Sensor Electronics
    • Sensor electronic interfaces, front-end electronics.
    • Analog/digital/mixed/RF/integrated circuit design, readout circuit, rectifier circuit, VLSI circuit.
    • Microwave and mm-wave circuits for sensors.
    • SoC-based sensor electronics: FPGA, MCU etc.
    • Electronics for data acquisition and signal processing in relation to sensors and their operation.
    • Models for sensor circuit simulation.
    • Sensor characterization circuits and methods—hardware implementation and performance analysis
  • Sensors Signal Processing
    • Analog signal processing: electronic circuits, radio, telephone, radar, and television systems.
    • Digital signal processing: digital circuits, ASICs, FPGA, DSP chips.
    • Audio, image, and video signal processing, compression and analysis.
    • Wireless communications: statistical channel modeling, waveform generation, filtering, optimal receiver design, modulation and demodulation techniques.
    • Array processing: sensors; antennas, radar, sonar, acoustic, anti-jamming and wireless communications; seismic exploration.
    • Signal quality improvement: noise reduction, image enhancement, and echo cancellation.
    • Computer vision: pattern recognition, digital geometry, and signal processing.
  • Potential Applications
    • Electrical power and energy systems, self-powered sensors, low-power devices, power amplifiers, energy harvesting, thermoelectric generators, etc.
    • Semiconductor devices.
    • Advanced electromechanical systems and control applications.
    • Electronic packaging.
    • Flexible/stretchable/printed electronics and sensors.
    • Multi-sensors fusion.
    • Biomedical and surgery.
    • Artificial senses, including electronic tongue, electronic nose.
    • Emergencies and alerts.
    • Verification and recognition.
    • Automotive sensors.
    • Structural health monitoring.
    • Instrumentation and measurement.

Prof. Dr. Youfan Hu
Prof. Dr. Serioja Ovidiu Tatu
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Sensors is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Published Papers (13 papers)

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Research

14 pages, 1689 KiB  
Article
Pathogen Detection via Impedance Spectroscopy-Based Biosensor
by Tharun Reddy Kandukuri, Ioannis Prattis, Pelumi Oluwasanya and Luigi G. Occhipinti
Sensors 2024, 24(3), 856; https://doi.org/10.3390/s24030856 - 28 Jan 2024
Viewed by 683
Abstract
This paper presents the development of a miniaturized sensor device for selective detection of pathogens, specifically Influenza A Influenza virus, as an enveloped virus is relatively vulnerable to damaging environmental impacts. In consideration of environmental factors such as humidity and temperature, this particular [...] Read more.
This paper presents the development of a miniaturized sensor device for selective detection of pathogens, specifically Influenza A Influenza virus, as an enveloped virus is relatively vulnerable to damaging environmental impacts. In consideration of environmental factors such as humidity and temperature, this particular pathogen proves to be an ideal choice for our study. It falls into the category of pathogens that pose greater challenges due to their susceptibility. An impedance biosensor was integrated into an existing platform and effectively separated and detected high concentrations of airborne pathogens. Bio-functionalized hydrogel-based detectors were utilized to analyze virus-containing particles. The sensor device demonstrated high sensitivity and specificity when exposed to varying concentrations of Influenza A virus ranging from 0.5 to 50 μg/mL. The sensitivity of the device for a 0.5 μg/mL analyte concentration was measured to be 695 Ω· mL/μg. Integration of this pathogen detector into a compact-design air quality monitoring device could foster the advancement of personal exposure monitoring applications. The proposed sensor device offers a promising approach for real-time pathogen detection in complex environmental settings. Full article
(This article belongs to the Special Issue Feature Papers in Electronic Sensors)
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16 pages, 5014 KiB  
Article
Non-Contact Current Measurement for Three-Phase Rectangular Busbars Using TMR Sensors
by Huafeng Su, Haojun Li, Weihao Liang, Chaolan Shen and Zheng Xu
Sensors 2024, 24(2), 388; https://doi.org/10.3390/s24020388 - 09 Jan 2024
Viewed by 539
Abstract
This paper proposes a non-contact current measurement method for three-phase rectangular busbars based on TMR (tunneling magneto-resistance) sensors, due to their advantages of large dynamic range, wide bandwidth, light weight, and easy installation. A non-contact current sensor composed of only three TMR sensors [...] Read more.
This paper proposes a non-contact current measurement method for three-phase rectangular busbars based on TMR (tunneling magneto-resistance) sensors, due to their advantages of large dynamic range, wide bandwidth, light weight, and easy installation. A non-contact current sensor composed of only three TMR sensors is developed and the TMR sensors are respectively placed at a location with a certain distance from the surface of each rectangular busbar to measure the magnetic fields generated by the busbar currents. To calibrate the developed current sensor, i.e., to establish the relationship between the magnetic fields measured by the TMR sensors and the currents flowing in the three-phase rectangular busbars, we designed a thyristor-controlled resistive load as a calibrator, which is connected to a downstream branch of the distribution cabinet. By switching the resistive load, a calibration current, which can be identified from the background current, is generated in one rectangular busbar and its value is measured at the location of the calibrator, and transmitted wirelessly to the location of the TMR sensors. A new and robust method is proposed to extract the voltage components, corresponding to the calibration current, from the voltage waveforms of the TMR sensors. By calculating the proportional coefficients between the calibration currents and the extracted voltage components, online calibration of the current sensor is achieved. We designed and implemented a current measurement system consisting of a current sensor using TMR sensors, a thyristor-controlled resistive load for current sensor calibration, and a data acquisition circuit based on a multi-channel analog-to-digital converter (ADC). Current measurement experiments were performed in a practical distribution cabinet installed in our laboratory. Compared to the measurement results using a commercial current probe with an accuracy of 1%, the relative error of the measured currents in RMS is less than 2.5% and the phase error is less than 1°, while the nonlinearity error of the current sensor is better than 0.8%. Full article
(This article belongs to the Special Issue Feature Papers in Electronic Sensors)
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14 pages, 5495 KiB  
Article
Echo Frequency Estimation Technology for Passive Surface Acoustic Wave Resonant Sensors Based on a Genetic Algorithm
by Yufen Wu, Yanling Li, Xue Wang, Jianchao Zhang and Jin Yang
Sensors 2023, 23(23), 9401; https://doi.org/10.3390/s23239401 - 25 Nov 2023
Viewed by 456
Abstract
Passive wireless surface acoustic wave (SAW) resonant sensors are widely used in measuring pressure, temperature, and torque, typically detecting sensing parameters by measuring the echo signal frequency of SAW resonators. Therefore, the accuracy of echo signal frequency estimation directly affects the performance index [...] Read more.
Passive wireless surface acoustic wave (SAW) resonant sensors are widely used in measuring pressure, temperature, and torque, typically detecting sensing parameters by measuring the echo signal frequency of SAW resonators. Therefore, the accuracy of echo signal frequency estimation directly affects the performance index of the sensor. Due to the exponential attenuation trend of the echo signal, the duration is generally approximately 10 μs, with conventional frequency domain analysis methods limited by the sampling frequency and data points. Thus, the resolution of frequency estimation is limited. Here, signal time-domain fitting combined with a genetic algorithm is used to estimate SAW echo signal frequency. To address the problem of slow estimation speed and poor timeliness caused by a conventional genetic algorithm, which needs to simultaneously estimate multiple parameters, such as signal amplitude, phase, frequency, and envelope, the Hilbert transform is proposed to remove the signal envelope and estimate its amplitude, and the fast Fourier transform subsection method is used to analyze the initial phase of the signal. The genetic algorithm is thereby optimized to realize the frequency estimation of SAW echo signals under a single parameter. The developed digital signal processing frequency detection system was monitored in real time to estimate the frequency of an SAW echo signal lasting 10 μs and found to have only 100 sampling points. The proposed method has a frequency estimation error within 3 kHz and a frequency estimation time of less than 1 s, which is eight times faster than the conventional genetic algorithm. Full article
(This article belongs to the Special Issue Feature Papers in Electronic Sensors)
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15 pages, 1050 KiB  
Article
Self-Position Determination Based on Array Signal Subspace Fitting under Multipath Environments
by Zhongkang Cao, Pan Li, Wanghao Tang, Jianfeng Li and Xiaofei Zhang
Sensors 2023, 23(23), 9356; https://doi.org/10.3390/s23239356 - 23 Nov 2023
Cited by 1 | Viewed by 615
Abstract
A vehicle’s position can be estimated with array receiving signal data without the help of satellite navigation. However, traditional array self-position determination methods are faced with the risk of failure under multipath environments. To deal with this problem, an array signal subspace fitting [...] Read more.
A vehicle’s position can be estimated with array receiving signal data without the help of satellite navigation. However, traditional array self-position determination methods are faced with the risk of failure under multipath environments. To deal with this problem, an array signal subspace fitting method is proposed for suppressing the multipath effect. Firstly, all signal incidence angles are estimated with enhanced spatial smoothing and root multiple signal classification (Root-MUSIC). Then, non-line-of-sight (NLOS) components are distinguished from multipath signals using a K-means clustering algorithm. Finally, the signal subspace fitting (SSF) function with a P matrix is established to reduce the NLOS components in multipath signals. Meanwhile, based on the initial clustering estimation, the search area can be significantly reduced, which can lead to less computational complexity. Compared with the C-matrix, oblique projection, initial signal fitting (ISF), multiple signal classification (MUSIC) and signal subspace fitting (SSF), the simulated experiments indicate that the proposed method has better NLOS component suppression performance, less computational complexity and more accurate positioning precision. A numerical analysis shows that the complexity of the proposed method has been reduced by at least 7.64dB. A cumulative distribution function (CDF) analysis demonstrates that the estimation accuracy of the proposed method is increased by 3.10dB compared with the clustering algorithm and 11.77dB compared with MUSIC, ISF and SSF under multipath environments. Full article
(This article belongs to the Special Issue Feature Papers in Electronic Sensors)
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14 pages, 3628 KiB  
Article
Flexible Sensors Array Based on Frosted Microstructured Ecoflex Film and TPU Nanofibers for Epidermal Pulse Wave Monitoring
by Xue Wang, Zhiping Feng, Gaoqiang Zhang, Luna Wang, Liang Chen, Jin Yang and Zhonglin Wang
Sensors 2023, 23(7), 3717; https://doi.org/10.3390/s23073717 - 03 Apr 2023
Cited by 2 | Viewed by 2287
Abstract
Recent advances in flexible pressure sensors have fueled increasing attention as promising technologies with which to realize human epidermal pulse wave monitoring for the early diagnosis and prevention of cardiovascular diseases. However, strict requirements of a single sensor on the arterial position make [...] Read more.
Recent advances in flexible pressure sensors have fueled increasing attention as promising technologies with which to realize human epidermal pulse wave monitoring for the early diagnosis and prevention of cardiovascular diseases. However, strict requirements of a single sensor on the arterial position make it difficult to meet the practical application scenarios. Herein, based on three single-electrode sensors with small area, a 3 × 1 flexible pressure sensor array was developed to enable measurement of epidermal pulse waves at different local positions of radial artery. The designed single sensor holds an area of 6 × 6 mm2, which mainly consists of frosted microstructured Ecoflex film and thermoplastic polyurethane (TPU) nanofibers. The Ecoflex film was formed by spinning Ecoflex solution onto a sandpaper surface. Micropatterned TPU nanofibers were prepared on a fluorinated ethylene propylene (FEP) film surface using the electrospinning method. The combination of frosted microstructure and nanofibers provides an increase in the contact separation of the tribopair, which is of great benefit for improving sensor performance. Due to this structure design, the single small-area sensor was characterized by pressure sensitivity of 0.14 V/kPa, a response time of 22 ms, a wide frequency band ranging from 1 to 23 Hz, and stability up to 7000 cycles. Given this output performance, the fabricated sensor can detect subtle physiological signals (e.g., respiration, ballistocardiogram, and heartbeat) and body movement. More importantly, the sensor can be utilized in capturing human epidermal pulse waves with rich details, and the consistency of each cycle in the same measurement is as high as 0.9987. The 3 × 1 flexible sensor array is employed to acquire pulse waves at different local positions of the radial artery. In addition, the time domain parameters including pulse wave transmission time (PTT) and pulse wave velocity (PWV) can be obtained successfully, which holds promising potential in pulse-based cardiovascular system status monitoring. Full article
(This article belongs to the Special Issue Feature Papers in Electronic Sensors)
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14 pages, 2664 KiB  
Article
Resistive-Based Micro-Kelvin Temperature Resolution for Ultra-Stable Space Experiments
by David Roma-Dollase, Vivek Gualani, Martin Gohlke, Klaus Abich, Jordan Morales, Alba Gonzalvez, Victor Martín, Juan Ramos-Castro, Josep Sanjuan and Miquel Nofrarias
Sensors 2023, 23(1), 145; https://doi.org/10.3390/s23010145 - 23 Dec 2022
Cited by 3 | Viewed by 2249
Abstract
High precision temperature measurements are a transversal need in a wide area of physical experiments. Space-borne gravitational wave detectors are a particularly challenging case, requiring both high precision and high stability in temperature measurement. In this contribution, we present a design able to [...] Read more.
High precision temperature measurements are a transversal need in a wide area of physical experiments. Space-borne gravitational wave detectors are a particularly challenging case, requiring both high precision and high stability in temperature measurement. In this contribution, we present a design able to reach 1 μK/Hz in most of the measuring band down to 1 mHz, and reaching 20 μK/Hz at 0.1 mHz. The scheme is based on resistive sensors in a Wheatstone bridge configuration which is AC modulated to minimize the 1/f noise. As a part of our study, we include the design of a test bench able to guarantee the high stability environment required for measurements. We show experimental results characterising both the test bench and the read-out, and discuss potential noise sources that may limit our measurement. Full article
(This article belongs to the Special Issue Feature Papers in Electronic Sensors)
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11 pages, 2313 KiB  
Article
A Flexible Pressure Sensor with a Mesh Structure Formed by Lost Hair for Human Epidermal Pulse Wave Monitoring
by Xue Wang, Zhiping Feng, Peng Li, Luna Wang, Liang Chen, Yufen Wu and Jin Yang
Sensors 2023, 23(1), 45; https://doi.org/10.3390/s23010045 - 21 Dec 2022
Cited by 3 | Viewed by 1594
Abstract
Flexible pressure sensors with the capability of monitoring human vital signs show broad application prospects in personalized healthcare. In this work, a hair-based flexible pressure sensor (HBPS) consisting of lost hair and polymer films was proposed for the continuous monitoring of the human [...] Read more.
Flexible pressure sensors with the capability of monitoring human vital signs show broad application prospects in personalized healthcare. In this work, a hair-based flexible pressure sensor (HBPS) consisting of lost hair and polymer films was proposed for the continuous monitoring of the human epidermal arterial pulse waveform. A macroscale mesh structure formed by lost hair provides a simplified spacer that endows the triboelectric-based flexible pressure sensor with sufficient contact–separation space. Based on this mesh structure design, the hair-based flexible pressure sensor can respond to the slight pressure change caused by an object with 5 mg weight and hold a stable output voltage under 1–30 Hz external pressure excitation. Additionally, the hair-based flexible pressure sensor showed great sensitivity (0.9 V/kPa) and decent stability after 4500 cycles of operation. Given these compelling features, the HBPS can successfully measure the human epidermal arterial pulses with obvious details at different arteries. The proposed HBPS can also be used to monitor the pulse signals of different subjects. Furthermore, the three different pulse wave transmission time (PTT) values (PTT-foot, PTT-middle, and PTT-peak) can be obtained by simultaneously monitoring human pulse and electrocardiogram signals, which has enormous application potential for assessing cardiovascular system health. Full article
(This article belongs to the Special Issue Feature Papers in Electronic Sensors)
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20 pages, 6585 KiB  
Article
Design of Precision-Aware Subthreshold-Based MOSFET Voltage Reference
by Shuzheng Mu and Pak Kwong Chan
Sensors 2022, 22(23), 9466; https://doi.org/10.3390/s22239466 - 03 Dec 2022
Cited by 1 | Viewed by 1706
Abstract
A new precision-aware subthreshold-based MOSFET voltage reference is presented in this paper. The circuit was implemented TSMC−40 nm process technology. It consumed 9.6 μW at the supply voltage of 1.2 V. In this proposed work, by utilizing subthreshold-based MOSFET instead of bipolar [...] Read more.
A new precision-aware subthreshold-based MOSFET voltage reference is presented in this paper. The circuit was implemented TSMC−40 nm process technology. It consumed 9.6 μW at the supply voltage of 1.2 V. In this proposed work, by utilizing subthreshold-based MOSFET instead of bipolar junction transistor (BJT), relatively lower power consumption was obtained in the design while offering comparable precision to that offered by its BJT counterpart. Through the proposed second-order compensation, it achieved the temperature coefficient (T.C.) of 3.0 ppm/°C in the TT corner case and a 200-sample Monte-Carlo T.C. of 12.51 ppm/°C from −40 °C to 90 °C. This shows robust temperature insensitivity. The process sensitivity of Vref without and with trimming was 2.85% and 0.75%, respectively. The power supply rejection (PSR) was 71.65 dB at 100 Hz and 52.54 dB at 10 MHz. The Figure-of-Merit (FOM) for the total variation in output voltage was comparable with representative BJT circuits and better than subthreshold-based MOSFET circuits. Due to low T.C., low process sensitivity, and simplicity of the circuit architecture, the proposed work will be useful for sensor circuits with stringent requirements or other analog circuits that require high precision applications. Full article
(This article belongs to the Special Issue Feature Papers in Electronic Sensors)
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43 pages, 24442 KiB  
Article
Synthesis of High-Input Impedance Electronically Tunable Voltage-Mode Second-Order Low-Pass, Band-Pass, and High-Pass Filters Based on LT1228 Integrated Circuits
by Hua-Pin Chen, Shih-Jun Chen and Chih-Yang Chang
Sensors 2022, 22(23), 9379; https://doi.org/10.3390/s22239379 - 01 Dec 2022
Cited by 1 | Viewed by 1663
Abstract
This paper introduces two new high-input impedance electronically tunable voltage-mode (VM) multifunction second-order architectures with band-pass (BP), low-pass (LP), and high-pass (HP) filters. Both proposed architectures have one input and five outputs, implemented employing three commercial LT1228 integrated circuits (ICs), two grounded capacitors, [...] Read more.
This paper introduces two new high-input impedance electronically tunable voltage-mode (VM) multifunction second-order architectures with band-pass (BP), low-pass (LP), and high-pass (HP) filters. Both proposed architectures have one input and five outputs, implemented employing three commercial LT1228 integrated circuits (ICs), two grounded capacitors, and five resistors. Both proposed architectures also feature one high-impedance input port and three low-impedance output ports for easy connection to other VM configurations without the need for VM buffers. The two proposed VM LT1228-based second-order multifunction filters simultaneously provide BP, LP, and HP filter transfer functions at Vo1, Vo2, and Vo3 output terminals. The pole angular frequencies and the quality factors of the two proposed VM LT1228-based second-order multifunction filters can be electronically and orthogonally adjusted by the bias currents from their corresponding commercial LT1228 ICs, and can be independently adjusted in special cases. In addition, both proposed VM LT1228-based second-order multifunction filters have two independent gain-controlled BP and LP filter transfer functions at Vo4 and Vo5 output terminals, respectively. Based on the three commercial LT1228 ICs and several passive components, simulations and experimental measurements are provided to verify the theoretical predictions and demonstrate the performance of the two proposed high-input impedance electronically tunable VM LT1228-based second-order multifunction filters. The measured input 1-dB power gain compression point (P1dB), third-order IMD (IMD3), third-order intercept (TOI) point, and spurious-free dynamic range (SFDR) of the first proposed filter were −7.1 dBm, −48.84 dBc, 4.133 dBm, and 45.02 dBc, respectively. The measured input P1dB, IMD3, TOI, and SFDR of the second proposed filter were −7 dBm, −49.65 dBc, 4.316 dBm, and 45.88 dBc, respectively. Both proposed filters use a topology synthesis method based on the VM second-order non-inverting/inverting HP filter transfer functions to generate the BP, LP and HP filter transfer functions simultaneously, making them suitable for applications in three-way crossover networks. Full article
(This article belongs to the Special Issue Feature Papers in Electronic Sensors)
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16 pages, 6851 KiB  
Article
Multi-Currency Integrated Serial Number Recognition Model of Images Acquired by Banknote Counters
by Woohyuk Jang, Chaewon Lee, Dae Sik Jeong, Kunyoung Lee and Eui Chul Lee
Sensors 2022, 22(22), 8612; https://doi.org/10.3390/s22228612 - 08 Nov 2022
Viewed by 2820
Abstract
The objective of this study was to establish an automated system for the recognition of banknote serial numbers by developing a deep learning (DL)-based optical character recognition framework. An integrated serial number recognition model for the banknotes of four countries (South Korea (KRW), [...] Read more.
The objective of this study was to establish an automated system for the recognition of banknote serial numbers by developing a deep learning (DL)-based optical character recognition framework. An integrated serial number recognition model for the banknotes of four countries (South Korea (KRW), the United States (USD), India (INR), and Japan (JPY)) was developed. One-channel image data obtained from banknote counters were used in this study. The dataset used for the multi-currency integrated serial number recognition contains about 150,000 images. The class imbalance problem and model accuracy were improved through data augmentation based on geometric transforms that consider the range of errors that occur when a bill is inserted into the counter. In addition, by fine-tuning the recognition network, it was confirmed that the performance was improved when the serial numbers of the banknotes of four countries were recognized instead of the serial number of a banknote from each country from a single-currency dataset, and the generalization performance was improved by training the model to recognize the diverse serial numbers of multiple currencies. Therefore, the proposed method shows that real-time processing of less than 30 ms per image and character recognition with 99.99% accuracy are possible, even though there is a tradeoff between inference speed and serial number recognition accuracy when data augmentation based on the characteristics of banknote counters and a 1-stage object detector for banknote serial number recognition is used. Full article
(This article belongs to the Special Issue Feature Papers in Electronic Sensors)
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11 pages, 1802 KiB  
Article
Anti-Blooming Clocking for Time-Delay Integration CCDs
by Denis Szymon Piechaczek, Olaf Schrey, Manuel Ligges, Bedrich Hosticka and Rainer Kokozinski
Sensors 2022, 22(19), 7520; https://doi.org/10.3390/s22197520 - 04 Oct 2022
Cited by 2 | Viewed by 1634
Abstract
This paper presents an investigation of the responsivity of a time-delay integration (TDI) charge-coupled device that employs anti-blooming clocking and uses a varying number of TDI stages. The influence of charge blooming caused by unused TDI stages in a TDI deployed selection scheme [...] Read more.
This paper presents an investigation of the responsivity of a time-delay integration (TDI) charge-coupled device that employs anti-blooming clocking and uses a varying number of TDI stages. The influence of charge blooming caused by unused TDI stages in a TDI deployed selection scheme is shown experimentally, and an anti-blooming clocking mechanism is analyzed. The impact of blooming on sensor characteristics, such as the responsivity, the conversion gain, and the signal-to-noise ratio, is investigated. A comparison of the measurements with and without this anti-blooming clocking mechanism is presented and discussed in detail. Full article
(This article belongs to the Special Issue Feature Papers in Electronic Sensors)
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16 pages, 4276 KiB  
Article
Electronic Tunability and Cancellation of Serial Losses in Wire Coils
by Roman Sotner, Jan Jerabek, Ladislav Polak, Radek Theumer and Lukas Langhammer
Sensors 2022, 22(19), 7373; https://doi.org/10.3390/s22197373 - 28 Sep 2022
Cited by 5 | Viewed by 1358
Abstract
This work presents a novel methodology to adjust the inductance of real coils (electronically) and to cancel out serial losses (up to tens or even hundreds of Ohms in practice) electronically. This is important in various fields of electromagnetic sensors (inductive sensors), energy [...] Read more.
This work presents a novel methodology to adjust the inductance of real coils (electronically) and to cancel out serial losses (up to tens or even hundreds of Ohms in practice) electronically. This is important in various fields of electromagnetic sensors (inductive sensors), energy harvesting, measurement and especially in the instrumentation of various devices. State-of-the-art methods do not solve the problem of cancellation of real serial resistance, which is the most important parasitic feature in low- and middle-frequency bands. In this case, the employment of serial negative resistance is not possible due to stability issues. To solve this issue, two solutions allowing the cancellation of serial resistance by the value of the passive element and an electronically adjustable parameter are introduced. The operational ranges are between 0.1 and 1 mH and 0.1 and 10 mH, valid in bandwidths from hundreds of Hz up to hundreds of kHz. The proposed concepts are experimentally tested in two applications: an electronically tunable oscillator of LC type and an electronically tunable band-pass RLC filter. The presented methodology offers significant improvements in the process of circuit design employing inductors and can be beneficially used for on-chip design, where serial resistance issues can be very significant. Full article
(This article belongs to the Special Issue Feature Papers in Electronic Sensors)
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17 pages, 4291 KiB  
Article
Advanced Impedance Spectroscopy for QCM Sensor in Liquid Medium
by Ioan Burda
Sensors 2022, 22(6), 2337; https://doi.org/10.3390/s22062337 - 17 Mar 2022
Cited by 10 | Viewed by 2409
Abstract
Technological evolution has allowed impedance analysis to become a versatile and efficient method for the precise measurement of the equivalent electrical parameters of the quartz crystal microbalance (QCM). By measuring the dissipation factor, or another equivalent electrical parameter, the QCM sensor provides access [...] Read more.
Technological evolution has allowed impedance analysis to become a versatile and efficient method for the precise measurement of the equivalent electrical parameters of the quartz crystal microbalance (QCM). By measuring the dissipation factor, or another equivalent electrical parameter, the QCM sensor provides access to the sample mass per unit area and its physical parameters, thus ensuring a detailed analysis. This paper aims to demonstrate the benefits of advanced impedance spectroscopy concerning the Butterworth–van Dyke (BVD) model for QCM sensors immersed with an electrode in a liquid medium. The support instrument in this study is a fast and accurate software-defined virtual impedance analyzer (VIA) with real-time computing capabilities of the QCM sensor’s electric model. Advanced software methods of self-calibration, real-time compensation, innovative post-compensation, and simultaneous calculation by several methods are the experimental resources of the results presented in this paper. The experimental results validate the theoretical concepts and demonstrate both the capabilities of VIA as an instrument and the significant improvements brought by the advanced software methods of impedance spectroscopy analysis related to the BVD model. Full article
(This article belongs to the Special Issue Feature Papers in Electronic Sensors)
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