Open AccessFeature PaperArticle
A Microcontroller-Based Adaptive Model Predictive Control Platform for Process Control Applications
Electronics 2017, 6(4), 88; doi:10.3390/electronics6040088 (registering DOI) -
Abstract
Model predictive control (MPC) schemes employ dynamic models of a process within a receding horizon framework to optimize the behavior of a process. Although MPC has many benefits, a significant drawback is the large computational burden, especially in adaptive and constrained situations. In
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Model predictive control (MPC) schemes employ dynamic models of a process within a receding horizon framework to optimize the behavior of a process. Although MPC has many benefits, a significant drawback is the large computational burden, especially in adaptive and constrained situations. In this paper, a computationally efficient self-tuning/adaptive MPC scheme for a simple industrial process plant with rate and amplitude constraints on the plant input is developed. The scheme has been optimized for real-time implementation on small, low-cost embedded processors. It employs a short (2-step) control horizon with an adjustable prediction horizon, automatically tunes the move suppression (regularization) parameter to achieve well-conditioned control, and presents a new technique for generating the reference trajectory that is robust to changes in the process time delay and in the presence of any inverse response. In addition, the need for a full quadratic programming procedure to handle input constraints is avoided by employing a quasi-analytical solution that optimally fathoms the constraints. Preliminary hardware-in-the-loop (HIL) test results indicate that the resulting scheme performs well and has low implementation overhead. Full article
Open AccessFeature PaperReview
Smart E-Beam for Defect Identification & Analysis in the Nanoscale Technology Nodes: Technical Perspectives
Electronics 2017, 6(4), 87; doi:10.3390/electronics6040087 (registering DOI) -
Abstract
Optical beam has been the veteran inspector of semiconductor wafer production house, ever since the birth of integrated circuit (IC). As technology and market place raise the bar on chip density, Moore’s law stretches to the limit. Due to its inherent physical limitations,
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Optical beam has been the veteran inspector of semiconductor wafer production house, ever since the birth of integrated circuit (IC). As technology and market place raise the bar on chip density, Moore’s law stretches to the limit. Due to its inherent physical limitations, the optical method just cannot see the measuring rod of silicon industry getting recalibrated to finer nano-scales. Electron Beam Inspection (EBI), by virtue of its high resolution, has started to rule the nodes at 10 nm and below. As the geometries shrink, defects can reside deep within the structures. EBI can find those tiny defects, which otherwise go scot-free with optical tools. However, EBI suffers the handicap of poor performance and low throughput. It is therefore essential to complement EBI by judiciously crafting out the methods for getting the desired performance, a subject matter to which, this article is committed to. The research torchlights the critical EBI throughput problem to round-up “care-areas”. Such guided and focused inspection augments throughput, thereby positioning EBI as the industrial grade candidate in finer nanometer segment. Besides gearing up to current trends, the smart EBI school of thought is inspirational, to fuel the aspirations for 1 nanometer scale. Full article
Open AccessFeature PaperReview
Frequency and Polarization-Diversified Linear Sampling Methods for Microwave Tomography and Remote Sensing Using Electromagnetic Metamaterials
Electronics 2017, 6(4), 85; doi:10.3390/electronics6040085 -
Abstract
Metamaterial leaky wave antennas (MTM-LWAs), one kind of frequency scanning antennas, exhibit frequency-space mapping characteristics that can be utilized to obtain a sufficient field of view (FOV) and reconstruct shapes in both remote sensing and microwave imaging. In this article, we utilize MTM-LWAs
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Metamaterial leaky wave antennas (MTM-LWAs), one kind of frequency scanning antennas, exhibit frequency-space mapping characteristics that can be utilized to obtain a sufficient field of view (FOV) and reconstruct shapes in both remote sensing and microwave imaging. In this article, we utilize MTM-LWAs to conduct a spectrally encoded three-dimensional (3D) microwave tomography and remote sensing that can reconstruct conductive targets with various dimensions. In this novel imaging technique, we employ the linear sampling method (LSM) as a powerful and fast reconstruction approach. Unlike the traditional LSM using only one single frequency to illuminate a fixed direction, the proposed method utilizes a frequency scanning MTM antenna array able to accomplish frequency-space mapping over the targeted 3D background that includes unknown objects. In addition, a novel technique based on a frequency and polarization hybrid method is proposed to improve the shape reconstruction resolution and stability in ill-posed inverse problems. Both simulation and experimental results demonstrate the unique advantages of the proposed LSM using MTM-LWAs with frequency and polarization diversity as an efficient 3D remote sensing and tomography scheme. Full article
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Open AccessFeature PaperArticle
The Electrical Properties of Plasma-Deposited Thin Films Derived from Pelargonium graveolens
Electronics 2017, 6(4), 86; doi:10.3390/electronics6040086 -
Abstract
Inherently volatile at atmospheric pressure and room temperature, plant-derived precursors present an interesting human-health-friendly precursor for the chemical vapour deposition of thin films. The electrical properties of films derived from Pelargonium graveolens (geranium) were investigated in metal–insulator–metal (MIM) structures. Thin polymer-like films were
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Inherently volatile at atmospheric pressure and room temperature, plant-derived precursors present an interesting human-health-friendly precursor for the chemical vapour deposition of thin films. The electrical properties of films derived from Pelargonium graveolens (geranium) were investigated in metal–insulator–metal (MIM) structures. Thin polymer-like films were deposited using plasma-enhanced synthesis under various plasma input power. The J–V characteristics of thus-fabricated MIM were then studied in order to determine the direct current (DC) conduction mechanism of the plasma polymer layers. It was found that the capacitance of the plasma-deposited films decreases at low frequencies (C ≈ 10−11) and remains at a relatively constant value (C ≈ 10−10) at high frequencies. These films also have a low dielectric constant across a wide range of frequencies that decreases as the input RF power increases. The conductivity was determined to be around 10−16–10−17 Ω−1 m−1, which is typical for insulating materials. The Richardson–Schottky mechanism might dominate charge transport in the higher field region for geranium thin films. Full article
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Open AccessArticle
Data-Driven ECG Denoising Techniques for Characterising Bipolar Lead Sets along the Left Arm in Wearable Long-Term Heart Rhythm Monitoring
Electronics 2017, 6(4), 84; doi:10.3390/electronics6040084 -
Abstract
Abnormal heart rhythms (arrhythmias) are a major cause of cardiovascular disease and death in Europe. Sudden cardiac death accounts for 50% of cardiac mortality in developed countries; ventricular tachycardia or ventricular fibrillation is the most common underlying arrhythmia. In the ambulatory population, atrial
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Abnormal heart rhythms (arrhythmias) are a major cause of cardiovascular disease and death in Europe. Sudden cardiac death accounts for 50% of cardiac mortality in developed countries; ventricular tachycardia or ventricular fibrillation is the most common underlying arrhythmia. In the ambulatory population, atrial fibrillation is the most common arrhythmia and is associated with an increased risk of stroke and heart failure, particularly in an aging population. Early detection of arrhythmias allows appropriate intervention, reducing disability and death. However, in the early stages of disease arrhythmias may be transient, lasting only a few seconds, and are thus difficult to detect. This work addresses the problem of extracting the far-field heart electrogram signal from noise components, as recorded in bipolar leads along the left arm, using a data driven ECG (electrocardiogram) denoising algorithm based on ensemble empirical mode decomposition (EEMD) methods to enable continuous non-invasive monitoring of heart rhythm for long periods of time using a wrist or arm wearable device with advanced biopotential sensors. Performance assessment against a control denoising method of signal averaging (SA) was implemented in a pilot study with 34 clinical cases. EEMD was found to be a reliable, low latency, data-driven denoising technique with respect to the control SA method, achieving signal-to-noise ratio (SNR) enhancement to a standard closer to the SA control method, particularly on the upper arm-ECG bipolar leads. Furthermore, the SNR performance of the EEMD was improved when assisted with an FFT (fast Fourier transform ) thresholding algorithm (EEMD-fft). Full article
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Open AccessArticle
Accuracy Analysis Comparison of Supervised Classification Methods for Anomaly Detection on Levees Using SAR Imagery
Electronics 2017, 6(4), 83; doi:10.3390/electronics6040083 -
Abstract
This paper analyzes the use of a synthetic aperture radar (SAR) imagery to support levee condition assessment by detecting potential slide areas in an efficient and cost-effective manner. Levees are prone to a failure in the form of internal erosion within the earthen
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This paper analyzes the use of a synthetic aperture radar (SAR) imagery to support levee condition assessment by detecting potential slide areas in an efficient and cost-effective manner. Levees are prone to a failure in the form of internal erosion within the earthen structure and landslides (also called slough or slump slides). If not repaired, slough slides may lead to levee failures. In this paper, we compare the accuracy of the supervised classification methods minimum distance (MD) using Euclidean and Mahalanobis distance, support vector machine (SVM), and maximum likelihood (ML), using SAR technology to detect slough slides on earthen levees. In this work, the effectiveness of the algorithms was demonstrated using quad-polarimetric L-band SAR imagery from the NASA Jet Propulsion Laboratory’s (JPL’s) uninhabited aerial vehicle synthetic aperture radar (UAVSAR). The study area is a section of the lower Mississippi River valley in the Southern USA, where earthen flood control levees are maintained by the US Army Corps of Engineers. Full article
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Open AccessFeature PaperReview
A Review on Opportunities To Assess Hydration in Wireless Body Area Networks
Electronics 2017, 6(4), 82; doi:10.3390/electronics6040082 -
Abstract
The study of human body hydration is increasingly leading to new practical applications, including online assessment techniques for whole body water level and novel techniques for real time assessment methods as well as characterization for fitness and exercise performance. In this review, we
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The study of human body hydration is increasingly leading to new practical applications, including online assessment techniques for whole body water level and novel techniques for real time assessment methods as well as characterization for fitness and exercise performance. In this review, we will discuss the different techniques for assessing hydration from electrical properties of tissues and their components and the biological relations between tissues. This will be done mainly in the context of engineering while highlighting some applications in medicine, mobile health and sports. Full article
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Open AccessFeature PaperArticle
Subsecond Tsunamis and Delays in Decentralized Electronic Systems
Electronics 2017, 6(4), 80; doi:10.3390/electronics6040080 -
Abstract
Driven by technological advances and economic gain, society’s electronic systems are becoming larger, faster, more decentralized and autonomous, and yet with increasing global reach. A prime example are the networks of financial markets which—in contrast to popular perception—are largely all-electronic and decentralized with
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Driven by technological advances and economic gain, society’s electronic systems are becoming larger, faster, more decentralized and autonomous, and yet with increasing global reach. A prime example are the networks of financial markets which—in contrast to popular perception—are largely all-electronic and decentralized with no top-down real-time controller. This prototypical system generates complex subsecond dynamics that emerge from a decentralized network comprising heterogeneous hardware and software components, communications links, and a diverse ecology of trading algorithms that operate and compete within this all-electronics environment. Indeed, these same technological and economic drivers are likely to generate a similarly competitive all-electronic ecology in a variety of future cyberphysical domains such as e-commerce, defense and the transportation system, including the likely appearance of large numbers of autonomous vehicles on the streets of many cities. Hence there is an urgent need to deepen our understanding of stability, safety and security across a wide range of ultrafast, large, decentralized all-electronic systems—in short, society will eventually need to understand what extreme behaviors can occur, why, and what might be the impact of both intentional and unintentional system perturbations. Here we set out a framework for addressing this issue, using a generic model of heterogeneous, adaptive, autonomous components where each has a realistic limit on the amount of information and processing power available to it. We focus on the specific impact of delayed information, possibly through an accidental shift in the latency of information transmission, or an intentional attack from the outside. While much remains to be done in terms of developing formal mathematical results for this system, our preliminary results indicate the type of impact that can occur and the structure of a mathematical theory which may eventually describe it. Full article
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Open AccessArticle
System of Surface Defect Monitoring Based on a Distributed Crack Sensor
Electronics 2017, 6(4), 81; doi:10.3390/electronics6040081 -
Abstract
In this paper, we propose a method for monitoring surface defects like cracks in highly loaded structures. This method is based on the ability of surface cracks to open under the influence of external loads, thus causing the appearance of stresses and tears
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In this paper, we propose a method for monitoring surface defects like cracks in highly loaded structures. This method is based on the ability of surface cracks to open under the influence of external loads, thus causing the appearance of stresses and tears in the sensitive element—thin films that were deposited on the surface of the test object. We developed a system for monitoring surface defects based on a distributed crack sensor, the functional scheme of the sensor and its design, the structural scheme and algorithm of the system operation, and its model as a VHDL (VHSIC (Very high speed integrated circuits) Hardware Description Language)-description. Full article
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Open AccessArticle
Analysis of the Effect of Channel Leakage on Design, Characterization and Modelling of a High Voltage Pseudo-Floating Gate Sensor-Front-End
Electronics 2017, 6(4), 79; doi:10.3390/electronics6040079 -
Abstract
In this paper, we analyze the effects of channel leakage on the design, modelling and characterization of a high voltage pseudo-floating gate amplifier (PFGA) used as sensor front-end. Leakages are known as a major challenge in new modern CMOS technologies, which are used
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In this paper, we analyze the effects of channel leakage on the design, modelling and characterization of a high voltage pseudo-floating gate amplifier (PFGA) used as sensor front-end. Leakages are known as a major challenge in new modern CMOS technologies, which are used to bias the PFGA, and consequently affect the behavior of the amplifier. As high voltages are desired for actuation of many types of resonating sensors, especially in ultrasound applications, PFGA implemented in high voltage and low leakage technologies, such as older CMOS fabrication processes or power MOSFET can be the only option. The challenge with these technologies used to implement the PFGA is that the leakages are very low, which affect the biasing of the floating gate. However, the numerous advantages of this type of amplifier, implemented with modern fabrication processes, such as high flexibility, compactness, low power consumption , etc. encouraged the authors to research about this topic. This work provides analysis of the working principle and the design rules for this amplifier, emphasizing the major differences between PFGA implemented in low leakage and high leakage technologies. Static and dynamic analysis, input offset and non-linearity of the PFGA are the main topics of this article. Three different design approaches are presented in this paper, in order to provide a more general design procedure and offset compensation for any low leakage PFGA. The amplifier has been simulated in AMS-0.35μm CMOS models for supply voltages of 5 V and 10 V. Two prototypes have been realized to verify the validity of the modelling and the simulation results. Both devices have been realized by using discrete components and mounted on a printed circuit board. In this work, MOSFETs are realized by using commercial IC CD4007UB and 2N7000. Measurement results of the first prototype proved that the implementation of a low leakage PFGA is possible after that the input offset of the amplifier has been compensated. Measurement results of the second prototype have been used to characterize the low leakage PFGA, extracting the best performances from this amplifier, realized with less components and providing a more compact device. Finally, design rules have been summarized in order to implement this amplifier, which enjoys compactness and a relative low power dissipation. Full article
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Open AccessArticle
Integrated Circuit Conception: A Wire Optimization Technic Reducing Interconnection Delay in Advanced Technology Nodes
Electronics 2017, 6(4), 78; doi:10.3390/electronics6040078 -
Abstract
As we increasingly use advanced technology nodes to design integrated circuits (ICs), physical designers and electronic design automation (EDA) providers are facing multiple challenges, firstly, to honor all physical constraints coming with cutting-edge technologies and, secondly, to achieve expected quality of results (QoR).
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As we increasingly use advanced technology nodes to design integrated circuits (ICs), physical designers and electronic design automation (EDA) providers are facing multiple challenges, firstly, to honor all physical constraints coming with cutting-edge technologies and, secondly, to achieve expected quality of results (QoR). An advanced technology should be able to bring better performances with minimum cost whatever the complexity. A high effort to develop out-of-the-box optimization techniques is more than needed. In this paper, we will introduce a new routing technique, with the objective to optimize timing, by only acting on routing topology, and without impacting the IC Area. In fact, the self-aligned double patterning (SADP) technology offers an important difference on layer resistance between SADP and No-SADP layers; this property will be taken as an advantage to drive the global router to use No-SADP less resistive layers for critical nets. To prove the benefit on real test cases, we will use Mentor Graphics’ physical design EDA tool Nitro-SoC™ and several 7 nm technology node designs. The experiments show that worst negative slack (WNS) and total negative slack (TNS) improved up to 13% and 56%, respectively, compared to the baseline flow. Full article
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Open AccessFeature PaperArticle
Study of the Contributions of Donor and Acceptor Photoexcitations to Open Circuit Voltage in Bulk Heterojunction Organic Solar Cells
Electronics 2017, 6(4), 75; doi:10.3390/electronics6040075 -
Abstract
One of the key parameters in determining the power conversion efficiency (PCE) of bulk heterojunction (BHJ) organic solar cells (OSCs) is the open circuit voltage . The processes of exciting the donor and acceptor materials individually in a BHJ OSC are investigated and
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One of the key parameters in determining the power conversion efficiency (PCE) of bulk heterojunction (BHJ) organic solar cells (OSCs) is the open circuit voltage . The processes of exciting the donor and acceptor materials individually in a BHJ OSC are investigated and are found to produce two different expressions for . Using the contributions of electron and hole quasi-Fermi levels and charge carrier concentrations, the two different expressions are derived as functions of the energetics of the donor and acceptor materials and the photo-generated charge carrier concentrations, and calculated for a set of donor-acceptor blends. The simultaneous excitation of both the donor and acceptor materials is also considered and the corresponding , which is different from the above two, is derived. The calculated from the photoexcitation of the donor is found to be somewhat comparable with that obtained from the photoexcitation of the acceptor in most combinations of the donor and acceptor materials considered here. It is also found that the calculated from the simultaneous excitations of donor and acceptor in BHJ OSCs is also comparable with the other two . All three thus derived produce similar results and agree reasonably well with the measured values. All three depend linearly on the concentration of the photoexcited charge carriers and hence incident light intensity, which agrees with experimental results. The outcomes of this study are expected to help in finding materials that may produce higher and hence enhanced PCE in BHJ OSCs. Full article
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Open AccessArticle
Quiet Zone Enhancement for a Target Location Using an Improved Virtual Sensing Algorithm
Electronics 2017, 6(4), 76; doi:10.3390/electronics6040076 -
Abstract
Generating a quiet zone at a target location is the ultimate goal of active noise control (ANC). Generally, the best noise cancellation is achieved at the locations of error sensors. However, the distribution of physical error sensors at a given location is not
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Generating a quiet zone at a target location is the ultimate goal of active noise control (ANC). Generally, the best noise cancellation is achieved at the locations of error sensors. However, the distribution of physical error sensors at a given location is not always convenient or feasible. To overcome this challenge, a number of virtual sensing algorithms for ANC have been researched. Using the physical error signals and knowledge of the system, the adaptive least mean square (LMS) virtual sensing algorithm estimates the error signal at a location that is remote from the physical error sensor, referred to as the virtual location. It achieves excellent performance under the assumption that the unknown primary path is fixed, but its performance decreases significantly if the path is constantly changing. This paper presents a real-time ANC system with an improved virtual sensing algorithm to solve this problem. The proposed system was tested to enhance the quiet zone in a constantly changing environment; an enhanced quiet zone was created, and the noise cancellation, especially at the target location, obviously improved. Full article
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Open AccessFeature PaperArticle
A Nonlinear Drift Memristor Model with a Modified Biolek Window Function and Activation Threshold
Electronics 2017, 6(4), 77; doi:10.3390/electronics6040077 -
Abstract
The main idea of the present research is to propose a new memristor model with a highly nonlinear ionic drift suitable for computer simulations of titanium dioxide memristors for a large region of memristor voltages. For this purpose, a combination of the original
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The main idea of the present research is to propose a new memristor model with a highly nonlinear ionic drift suitable for computer simulations of titanium dioxide memristors for a large region of memristor voltages. For this purpose, a combination of the original Biolek window function and a weighted sinusoidal window function is applied. The new memristor model is based both on the Generalized Boundary Condition Memristor (GBCM) Model and on the Biolek model, but it has an improved property—an increased extent of nonlinearity of the ionic drift due to the additional weighted sinusoidal window function. The modified memristor model proposed here is compared with the Pickett memristor model, which is used here as a reference model. After that, the modified Biolek model is adjusted so that its basic relationships are made almost identical with these of the Pickett model. After several simulations of our new model, it is established that its behavior is similar to the realistic Pickett model but it operates without convergence problems and due to this, it is also appropriate for computer simulations. The modified memristor model proposed here is also compared with the Joglekar memristor model and several advantages of the new model are established. Full article
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Open AccessFeature PaperArticle
Microstrip Patch Antenna Assisted Compact Dual Band Planar Crossover
Electronics 2017, 6(4), 74; doi:10.3390/electronics6040074 -
Abstract
In Microwave Monolithic Integrated Circuits, crossovers maintain signal purity when transmission lines overlap with each other. A simple crossover for dual band applications, particularly suitable for the development of smart antennas, is presented in this paper. Derived from conventional patch antenna, the proposed
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In Microwave Monolithic Integrated Circuits, crossovers maintain signal purity when transmission lines overlap with each other. A simple crossover for dual band applications, particularly suitable for the development of smart antennas, is presented in this paper. Derived from conventional patch antenna, the proposed crossovers are easy to design and fabricate, thus reducing the overall complexity. Design is verified for a dual band crossover at 2.4/5.23 GHz on FR4 (Fiberglass Reinforced) epoxy and tested using Keysight E5080 A Vector Network Analyser. The results obtained by simulation and measurement are in agreement. The proposed crossovers find application in a Butler matrix for phased array and smart antenna systems. Full article
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Open AccessFeature PaperArticle
Pipelined Architecture of Multi-Band Spectral Subtraction Algorithm for Speech Enhancement
Electronics 2017, 6(4), 73; doi:10.3390/electronics6040073 -
Abstract
In this paper, a new pipelined architecture of the multi-band spectral subtraction algorithm has been proposed for real-time speech enhancement. The proposed hardware has been implemented on field programmable gate array (FPGA) device using Xilinx system generator (XSG), high-level programming tool, and Nexys-4
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In this paper, a new pipelined architecture of the multi-band spectral subtraction algorithm has been proposed for real-time speech enhancement. The proposed hardware has been implemented on field programmable gate array (FPGA) device using Xilinx system generator (XSG), high-level programming tool, and Nexys-4 development board. The multi-band algorithm has been developed to reduce the additive colored noise that does not uniformly affect the entire frequency band of useful signal. All the algorithm steps have been successfully implemented on hardware. Pipelining has been employed on this hardware architecture to increase the data throughput. Speech enhancement performances obtained by the hardware architecture are compared to those obtained by MATLAB simulation using simulated and actual noises. The resource utilization, the maximum operating frequency, and power consumption are reported for a low-cost Artix-7 FPGA device. Full article
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Open AccessArticle
Proactive Redundant Data Filtering Scheme for Combined RFID and Sensor Networks
Electronics 2017, 6(4), 72; doi:10.3390/electronics6040072 -
Abstract
Radio Frequency Identification (RFID) is gaining significant thrust in many application fields such as identification and real-time localization systems. Consequently, nowadays, the demand for integrated RFID-Sensors networks is increasing. Usually, numerous RFID-Sensors are deployed to form such types of networks. Then, an RFID
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Radio Frequency Identification (RFID) is gaining significant thrust in many application fields such as identification and real-time localization systems. Consequently, nowadays, the demand for integrated RFID-Sensors networks is increasing. Usually, numerous RFID-Sensors are deployed to form such types of networks. Then, an RFID tag can be located in the reading field of more than one reader that generates duplicated data reception at the base station. The data redundancy transmission causes unnecessary energy consumption and network overloading that contributes to the augmentation of transmission delays. In this paper, we tackle the data duplication reception problem. We propose an efficient and proactive filtering scheme for redundant data based on a preliminary broadcast. Our scheme allows us to prevent and significantly reduce the redundant data and improve the performances of the integrated RFID-sensor network. Full article
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Open AccessFeature PaperArticle
Through-Wall Single and Multiple Target Imaging Using MIMO Radar
Electronics 2017, 6(4), 70; doi:10.3390/electronics6040070 -
Abstract
The ability to perform target detection through walls and barriers is important for law enforcement, homeland security, and search and rescue teams. Multiple-input-multiple-output (MIMO) radar provides an improvement over traditional phased array radars for through-wall imaging. By transmitting independent waveforms from a transmit
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The ability to perform target detection through walls and barriers is important for law enforcement, homeland security, and search and rescue teams. Multiple-input-multiple-output (MIMO) radar provides an improvement over traditional phased array radars for through-wall imaging. By transmitting independent waveforms from a transmit array to a receive array, an effective virtual array is created. This array has improved degrees of freedom over phased arrays and mono-static MIMO systems. This virtual array allows us to achieve the same effective aperture length as a phased array with a lower number of elements because the virtual array can be described as the convolution of transmit and receive array positions. In addition, data from multiple walls of the same room can be used to collect target information. If two walls are perpendicular to each other and the geometry of transmit and receive arrays is known, then data can be processed independently of each other. Since the geometry of the arrays is known, a target scene can be created where the two data sets overlap. The overlapped scene can then be processed so that image artifacts that do not correlate between the data sets can be excised. The result gives improved target detection, reduction in false alarms, robustness to noise, and robustness against errors such as improperly aligned antennas. This paper explores MIMO radar techniques for target detection and localization behind building walls and addresses different mitigation techniques, such as a singular value decomposition of wavelet transform method to improve localization and detection of targets. Together, these techniques demonstrate methods that show a reduction in size and complexity of traditional through-wall radar systems while still providing accurate detection and localization. The use of the range migration algorithm in single and multi-target scenarios is shown to provide adequate imaging of through the wall targets in near and far field. Also, a multi-view algorithm is used to provide improved target detection and localization by fusing together multiple wall views. Full article
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Open AccessArticle
Low-Cost Fuzzy Logic Control for Greenhouse Environments with Web Monitoring
Electronics 2017, 6(4), 71; doi:10.3390/electronics6040071 -
Abstract
The design and implementation of a low-cost system for monitoring and remote control of a greenhouse using fuzzy logic is presented. For the control system, an Arduino Mega board was programmed with a fuzzy algorithm to monitor and perform control actions for environmental
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The design and implementation of a low-cost system for monitoring and remote control of a greenhouse using fuzzy logic is presented. For the control system, an Arduino Mega board was programmed with a fuzzy algorithm to monitor and perform control actions for environmental temperature, soil moisture, relative humidity, and lighting. A website was designed to visualize the main indicators of agricultural interest and to get access to tools such as forced ventilation, misting systems, and sprinkler irrigation. For connectivity to the webpage, an Arduino Ethernet Shield was used. Thus, it was possible to establish a local area network and monitor and control the greenhouse climate variables manually or automatically. The application designed allowed access to the configuration, monitoring, and control of climatic conditions in the greenhouse. The effectiveness of fuzzy logic to control nonlinear systems was therefore verified without the mathematical model of the plant. Thus, the use of resources for a gable roof greenhouse prototype was optimized. Full article
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Open AccessFeature PaperArticle
Logic Locking Using Hybrid CMOS and Emerging SiNW FETs
Electronics 2017, 6(3), 69; doi:10.3390/electronics6030069 -
Abstract
The outsourcing of integrated circuit (IC) fabrication services to overseas manufacturing foundry has raised security and privacy concerns with regard to intellectual property (IP) protection as well as the integrity maintenance of the fabricated chips. One way to protect ICs from malicious attacks
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The outsourcing of integrated circuit (IC) fabrication services to overseas manufacturing foundry has raised security and privacy concerns with regard to intellectual property (IP) protection as well as the integrity maintenance of the fabricated chips. One way to protect ICs from malicious attacks is to encrypt and obfuscate the IP design by incorporating additional key gates, namely logic encryption or logic locking. The state-of-the-art logic encryption techniques certainly incur considerable performance overhead upon the genuine IP design. The focus of this paper is to leverage the unique property of emerging transistor technology on reducing the performance overhead as well as preserving the robustness of logic locking technique. We design the polymorphic logic gate using silicon nanowire field effect transistors (SiNW FETs) to replace the conventional Exclusive-OR (XOR)-based logic cone. We then evaluate the proposed technique based on security metric and performance overhead. Full article
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