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Instrumentation and Measurement, IEEE Transactions on

Issue 9 • Date Sept. 2011

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  • Table of contents

    Publication Year: 2011 , Page(s): C1 - 3005
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  • IEEE Transactions on Instrumentation and Measurement publication information

    Publication Year: 2011 , Page(s): C2
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  • Special Section on Applied Measurements for Power Systems

    Publication Year: 2011 , Page(s): 3006
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  • Fuzzy Metrology-Sound Approach to the Identification of Sources Injecting Periodic Disturbances in Electric Networks

    Publication Year: 2011 , Page(s): 3007 - 3017
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1676 KB) |  | HTML iconHTML  

    The identification of sources injecting periodic disturbances in electric systems is a critical point in the assessment of the electric power quality. The available methods, based on a deterministic approach, do not always provide correct results. Methods based on heuristic approaches, such as those based on a fuzzy inference system (FIS), provide better results but do not allow measurement uncertainty to be evaluated in a straightforward way. This paper applies a modified FIS to the identification of the sources producing periodic distortion in power systems. The method associates an index, provided together with its measurement uncertainty, to each load connected to a point of common coupling capable of assessing whether the load is injecting or suffering distortion and quantifying the severity of the injected or suffered distortion. View full abstract»

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  • Flicker Effect Analysis in Human Subjects: New Noninvasive Method for Next-Generation Flickermeter

    Publication Year: 2011 , Page(s): 3018 - 3025
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (861 KB) |  | HTML iconHTML  

    Flicker severity is a parameter defined in the Standard EN 50160 that involves both power quality and physiological features. Due to practical and theoretical reasons, the flickermeter described by the relevant International Standard may lead to incorrect results when used to correlate voltage variations with annoyance caused by fluctuations of light emitted by other types of lamps different from those based on the incandescent-filament principle. Therefore, its replacement is under consideration by some international organizations, given that this last type of lamps will no longer be available on the market starting next year. This paper aims at providing a contribution to the study of a new theory to be used for the design of next-generation flickermeters that must account for a wider variety of luminous sources. In particular, the research is focused on finding a new method for detecting human being annoyance in the presence of luminous flicker that is based on the measurement of the pupil diameter under flicker conditions. In this connection, this paper first investigates on the performance of an ad-hoc test system with the main goal to prove and evaluate its accuracy. Then, the results of tests on six volunteers are presented and discussed. View full abstract»

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  • State Estimation and Branch Current Learning Using Independent Local Kalman Filter With Virtual Disturbance Model

    Publication Year: 2011 , Page(s): 3026 - 3034
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1382 KB) |  | HTML iconHTML  

    This paper presents a generalized approach to the design of independent local Kalman filters (KFs) without communication to be used for state estimation in distributed generation-based power systems. The design procedure is based on an improved model of the virtual disturbance concept proposed in a previous work. The local KFs are then synthesized based only on local models of the power network and on the characteristics of the associated virtual disturbance. The proposed solution is applied to an interconnected power network. By choosing appropriate models for the virtual disturbance, the local KFs can be suited for both dc and ac distribution systems. It is shown for both cases that the local KF can infer the local states of the network, including the aggregated branch currents coming from the other buses. Simulation results show improved results with respect to the previous proposed modeling approach even when the subsystems present widely different dynamics. The herein presented approach is well suited for the agent-based decentralized control of microgrids. View full abstract»

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  • Design of Smart MVDC Power Grid Protection

    Publication Year: 2011 , Page(s): 3035 - 3046
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1841 KB) |  | HTML iconHTML  

    Improved reliability and safety of the medium-voltage dc power distribution systems on board of all electric ships are the objectives of this paper. The authors propose the integration of the self-healing capability against faults of the measurement system in power system fault detection and protection systems. While most of previous work in the literature focuses on either one aspect independently, here, the two are integrated. On one hand, our approach addresses also the case of concurrent power system fault and measurement system fault. On the other hand, the proposed approach must be capable of distinguishing between the two types of failure. The proposed architecture is based on exchange of information between energy conversion and measurement devices. This makes the impact of communication delays critical, so its analysis is provided for the proposed case study. The impact on the performance of the measurement validation and protection systems is derived and can provide hints on the design. The protection method used as case study consists in controlling power converters to ride through the power system fault while maintaining power supply to the vital loads. To overcome failures of the measurement system, invalid data were detected and reconstructed through their expected value. View full abstract»

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  • The Effects of Integration Intervals on Recursive RMS Value and Power Measurement in Nonsinusoidal Conditions

    Publication Year: 2011 , Page(s): 3047 - 3057
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (496 KB) |  | HTML iconHTML  

    The effects of integration intervals on recursive rms value and power measurement in the presence of nonsinusoidal conditions are considered. The presence of time measurement intervals of both fixed and variable durations is assumed. Suitable formulas to evaluate the errors introduced by the desynchronization of measurement interval for active and apparent powers, power factor, and voltage and current rms values are developed; formulas accounting the contributions to the error of the cross products between couples of components at different frequencies are also developed. Then, the errors are evaluated in the presence of smoothing of the results over a variable number of consecutive measurements by means of proper formulas. Some numerical and experimental case studies conclude the analysis showing the effects of the different contributions to the error and the improvements of accuracy that can be obtained by smoothing the results. View full abstract»

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  • Accountability in Smart Microgrids Based on Conservative Power Theory

    Publication Year: 2011 , Page(s): 3058 - 3069
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (514 KB) |  | HTML iconHTML  

    Smart microgrids offer a new challenging domain for power theories and metering techniques because they include a variety of intermittent power sources which positively impact on power flow and distribution losses but may cause voltage asymmetry and frequency variation. In smart microgrids, the voltage distortion and asymmetry in presence of poly-phase nonlinear loads can be also greater than in usual distribution lines fed by the utility, thus affecting measurement accuracy and possibly causing tripping of protections. In such a context, a reconsideration of power theories is required since they form the basis for supply and load characterization. A revision of revenue metering techniques is also suggested to ensure a correct penalization of the loads for their responsibility in generating reactive power, voltage asymmetry, and distortion. This paper shows that the conservative power theory provides a suitable background to cope with smart grids characterization and metering needs. Simulation and experimental results show the properties of the proposed approach. View full abstract»

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  • On the Use of IEEE 1588 in Existing IEC 61850-Based SASs: Current Behavior and Future Challenges

    Publication Year: 2011 , Page(s): 3070 - 3081
    Cited by:  Papers (25)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1335 KB) |  | HTML iconHTML  

    The International Electrotechnical Commission (IEC) 61850 standard describes the communication inside the substation automation system (SAS) setting the base for new interoperating devices that share information using the Ethernet network infrastructure. More recently, the request of time synchronization among SAS components for the timestamping of critical events or synchrophasor measurement has generated a very high interest in the IEC 61850 working group for distributed synchronization protocols like IEEE 1588. This paper analyzes the current situation, matching different implementations of the IEEE 1588, and their respective accuracy, with the requirements of typical SAS applications: from the millisecond synchronization accuracy required by fault recorder application to the microsecond required by the sampled values (SV). The main focus of this paper is on the integration of IEEE 1588 with real already existing systems, and the goal is the performance comparison of different architectures. For these reasons, experimental tests have been carried out using a real SAS network infrastructure [redundant gigabit optical fiber Ethernet network managed using rapid spanning tree protocol (RSTP)]. The results show that, under ideal conditions, the IEEE 1588 protocol can achieve synchronization accuracy slightly worse (80 ns) than legacy IRIG-B systems (15 ns). However, IEEE 1588 makes possible a great cabling reduction and a simplified maintenance when synchronization is directly transferred on the SAS system bus. On the other hand, experiments highlight that nodes connected through a legacy RSTP infrastructure, which does not support IEEE 1588 messages, can lose the time synchronization in the case of network traffic or reconfiguration of the network. Therefore, the integration of IEEE 1588 over existing IEC 61850 station bus is basically a tradeoff between installation costs and performance since it requires the replacement of already installed Ethernet infrastructure.- - In the last part, this paper analyses the challenges for the next SAS generation that has to combine on the same plants the high accuracy IEEE 1588 implementation with high-availability protocols based on IEC 62439. Since the lifetime of an SAS is more than ten years and the adoption of these technologies takes several years, some solutions that introduce synchronization and high-availability protocols guaranteeing compatibility with existing technologies have been analyzed, too. For instance, an adaptation block that (when attached to a high-availability network) reconstructs the interface signals (e.g., synchronization signals) required by traditional bay has been proposed. View full abstract»

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  • Three-Dimensional Nondestructive “Sampling” of Art Objects Using Acoustic Microscopy and Time–Frequency Analysis

    Publication Year: 2011 , Page(s): 3082 - 3109
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (4837 KB) |  | HTML iconHTML  

    The microsampling destructions, which are caused by the sampling procedures of analytical spectroscopic methods, are, in most cases, not permitted to art objects, which are extremely valuable, rare, and fragile. Consequently, the development of nondestructive analysis techniques becomes a necessity. In this paper, we present a technique and method for the nondestructive identification of the stratigraphic structure of the paint layers of art objects. Using acoustic microscopy, in combination with time-frequency representations, the continuous or discrete wavelet transform, or the Hilbert-Huang transform, the depth profile of the stratigraphy is determined. View full abstract»

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  • An Optimized Implementation of Phase Locked Loops for Grid Applications

    Publication Year: 2011 , Page(s): 3110 - 3119
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1363 KB) |  | HTML iconHTML  

    This paper presents an optimized digital implementation of phase locked loops (PLLs) for grid applications suitable for implementation in low-cost industrial devices. A robust PLL is crucial in most of power converter applications, particularly in distorted environments. That is, the phase estimation should not be affected by power quality phenomena, given by Standard EN 50160, such as harmonics, imbalance, line notching, and voltage sags. The PLL dynamics is optimized as follows. A notch filter inside the loop is implemented to enhance the steady-state filtering. The bandwidth is maximized to get a fast postfault retracking (transient response). As justified in this paper, this approach is very suitable for both single- and three-phase PLLs. A low-resource-consuming implementation of the digitally controlled oscillator is provided: A digital model based on an RC electronic oscillator implements the needed trigonometric functions. This reduces the needed digital resources without reducing the performance. The proposed PLLs have been implemented and tested in a fixed-point DSP TI TMS320LF2407. These PLLs have been tested using different distorted inputs. Experimental results show that fast and rippleless phase estimations are achieved by the proposed implementations. View full abstract»

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  • A Reinforcement-Learning-Based Fuzzy Compensator for a Microcontroller-Based Frequency Synthesizer/Vector Voltmeter

    Publication Year: 2011 , Page(s): 3120 - 3127
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (443 KB) |  | HTML iconHTML  

    This paper presents the development of an intelligent fuzzy-based compensation scheme, utilizing reinforcement learning methodology, which can be used to compensate the reading of an unknown voltage, in vector form. This compensator is implemented online, in real time, with an indigenously developed microcontroller-based scheme that can be used both as a frequency synthesizer and as a vector voltmeter. This frequency synthesizer/vector voltmeter is developed using a direct digital synthesis method for the frequency synthesizer and a synchronous detection technique for the vector voltmeter. The developed fuzzy compensator has been tested in both offline and online modes, and in both cases, it has been found to significantly improve the accuracy of the measurement compared to those obtained with an uncompensated vector voltmeter. It has been shown that the final compensated measurements are in close agreement with the true unknown voltages under measurement. View full abstract»

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  • Extensions of Compressed Imaging: Flying Sensor, Coded Mask, and Fast Decoding

    Publication Year: 2011 , Page(s): 3128 - 3139
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (978 KB) |  | HTML iconHTML  

    In this paper, we outline some recent advances and identify some open problems in compressed sensing (CS) for remote imaging and related imaging applications. We propose new approaches to compressed remote sensing and image reconstruction, which exploit redundant/overlapping measurements (RMs), multiplexing imaging (MI), and an effective iterative procedure for decoding in the recovery phase. The RM approach involves the concept of data fusion and applies a noiselet transform to a CS measurement matrix, followed by 2-D hexagonal jittered sampling and 1-D jitter-based circular sampling. The MI approach enlarges the field of regard of imaging and provides the compromise between the numbers of masks and detectors by taking advantage of the merits of previous single-pixel sequent imaging and multipixel parallel imaging. Finally, the new decoding method in the CS recovery stage combines Bregman-based nonlocal total variation with curvelet-active-set iteration. View full abstract»

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  • Numerical Analysis for Remote Identification of Materials With Magnetic Characteristics

    Publication Year: 2011 , Page(s): 3140 - 3152
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1827 KB) |  | HTML iconHTML  

    There is a variety of methods used for remote sensing of objects such as acoustic, ground penetration radar detection, electromagnetic induction spectroscopy, infrared imaging, thermal neutron activation, core four-pole resonance, neutron backscattering, X-ray backscattering, and magnetic anomaly. The method that has to be used can be determined by the type of material, geographical location (underground or water), etc. Recent studies have been concentrated on the improvement of the criteria such as sensing distances, accuracy, and power consumption. In this paper, anomalies created by materials with magnetic characteristics at the perpendicular component of the Earth magnetic field have been detected by using a KMZ51 anisotropic magnetoresistive sensor with high sensitivity and low power consumption, and also, the effects of physical properties of materials on magnetic anomaly have been investigated. By analyzing the graphics obtained by 2-D motion of the sensor over the material, the most appropriate mathematical curves and formulas have been determined. Based on the physical properties of the magnetic material, the variations of the variables constituting the formulas of the curves have been analyzed. The contribution of this paper is the use of the results of these analyses for the purpose of identification of an unknown magnetic material. This is a new approach for the detection and determination of materials with magnetic characteristics by sensing the variation at the perpendicular component of the Earth magnetic field. The identification process has been explained in detail in this paper. View full abstract»

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  • Wearable Mobility Monitoring Using a Multimedia Smartphone Platform

    Publication Year: 2011 , Page(s): 3153 - 3161
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (686 KB) |  | HTML iconHTML  

    Understanding mobility is important for effective clinical decision making in the area of physical rehabilitation. Ideally, a person's mobility profile in a nonclinical setting, such as the home or community, could be obtained. This profile would include the environment and context in which the mobility takes place. This paper introduces a novel wearable mobility monitoring system (WMMS) for an objective ubiquitous measurement of mobility. This prototype WMMS was created using a smartphone-based approach that allowed for an all-in-one WMMS. The wearable system is freely worn on a person's belt, such as a normal phone. The WMMS was designed to monitor a user's mobility state and to take a photograph when a change of state was detected. These photographs were used to identify the context of mobility events (i.e., using an elevator, walking up/down stairs, and type of walking surface). Validation of the proposed WMMS was performed with five able-bodied subjects performing a structured sequence of mobility tasks. System performance was evaluated by its ability to detect changes of state and the ability to identify context from the photographs. The WMMS demonstrated good potential for community mobility monitoring. View full abstract»

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  • Wide-Range Time-to-Digital Converter With 1-ps Single-Shot Precision

    Publication Year: 2011 , Page(s): 3162 - 3172
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (501 KB) |  | HTML iconHTML  

    A high-resolution time-to-digital converter (TDC) was designed and tested. The converter is based on the fundamental method of counting the full clock cycles of a low-phase-noise reference clock and using a single-stage interpolating method employing time-to-amplitude converters that are based on Miller integrators. Counters and other control logic were implemented on a field-programmable gate array, and the interpolation units were constructed using discrete components. The single-shot precision of the uncompensated converter is about 1.8 ps over a time interval range of 0 to 328 μs. Single-shot precision is limited by the nonlinearities of the interpolators. These measurement errors caused by the nonlinearities are systematic, and thus, precision can be improved to 1 ps by a simple integral nonlinearity compensation. Other important factors that contribute to single-shot precision are the N -cycle jitter of the reference clock and the noise generated by the TDC circuit itself. By careful design, these errors can be made small enough to achieve picosecond-level precision. View full abstract»

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  • A Nondestructive Method for Accurately Extracting Substrate Parameters of Arbitrary Doping Profile in Nanoscale VLSI

    Publication Year: 2011 , Page(s): 3173 - 3184
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1028 KB) |  | HTML iconHTML  

    In this paper, a new approach is presented for determining the substrate parameters of an arbitrary doping profile. It is general, technology independent, nonintrusive, and relies on simple direct-current measurements. A single measurement is required for uniform substrates, whereas two more measurements are needed for each additional layer in the multilayer case. Two different kernels are introduced for substrate resistance computation. One features a closed-form analytical solution of the Laplace equations defining the problem under study. The other relies on a geometric formulation of the current streamlines in order to compute the substrate resistance. Both simulations and measurements are exploited in order to show the validity of the proposed scheme. For measurements, data from literature are utilized and also data from a fabricated test chip. The results demonstrate that the proposed method succeeds in computing the substrate parameters fast and with high accuracy. In uniform substrates, the error falls to zero, whereas, in epitaxial substrates, the average error is kept bellow 4%. View full abstract»

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  • Phase Unwrapping Using Interlaced Fringes for Phase-Shifting Techniques

    Publication Year: 2011 , Page(s): 3185 - 3193
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (947 KB) |  | HTML iconHTML  

    A novel phase-unwrapping algorithm is proposed by using interlaced fringe in optical 3-D measurement. In the measurement, a four-step phase-shift method including four sinusoidal fringes with 90° phase shift is used. On top of these four fringes, an interlaced fringe is encoded. In the measurement, all these designed fringes are projected onto the tested object, and fringe images are acquired by charge-coupled device cameras. Then, four fringe-different images with zero-valued fringes can be obtained by subtracting the interlaced fringe image from the other four sinusoidal fringe images; thus, the position and the characteristic of each fringe can be distinguished. Combined with the composition of the encoding interlaced fringe, the order of the fringes can be obtained. The whole process needs only one assistant interlaced fringe image. Experiment result shows that the proposed algorithm can get the 3-D information rapidly and exactly and has more robustness. View full abstract»

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  • Wireless Measurement of RFID IC Impedance

    Publication Year: 2011 , Page(s): 3194 - 3206
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (553 KB) |  | HTML iconHTML  

    Accurate knowledge of the input impedance of a radio-frequency identification (RFID) integrated circuit (IC) at its wake-up power is valuable as it enables the design of a performance-optimized tag for a specific IC. However, since the IC impedance is power dependent, few methods exist to measure it without advanced equipment. We propose and demonstrate a wireless method, based on electromagnetic simulation and threshold power measurement, applicable to fully assembled RFID tags, to determine the mounted IC's input impedance in the absorbing state, including any parasitics arising from the packaging and the antenna-IC connection. The proposed method can be extended to measure the IC's input impedance in the modulating state as well. View full abstract»

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  • Performance of a Compact Dual Six-Port Millimeter-Wave Network Analyzer

    Publication Year: 2011 , Page(s): 3207 - 3213
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (443 KB) |  | HTML iconHTML  

    This paper presents a millimeter-wave network analyzer incorporating two six-port correlators for the measurement of the reflection and transmission coefficients of a device under test in the frequency band 59-61 GHz. An instrumentation integrating the hardware and software resources, including advantages such as robustness, compactness, relatively low cost, small size, and real-time operation, is developed. The millimeter-wave part of the system is implemented on a thin alumina ceramic substrate. The proposed solution eliminates the need for complex heterodyne schemes and for bulky tuning mechanisms generally found in dual six-port network analyzers. Associated to this system, an explicit calibration procedure is proposed. The performance, in terms of measurement accuracy, is evaluated by comparing the results obtained from the system proposed with those given by a conventional network analyzer. View full abstract»

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  • A Reconfigurable Multichannel Capacitive Sensor Array Interface

    Publication Year: 2011 , Page(s): 3214 - 3221
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (708 KB) |  | HTML iconHTML  

    The design of a reconfigurable capacitive sensor array interface comprised of a subsystem able to read an array of capacitive-type sensors and an embedded processor is described. Each sensor is connected to a ring oscillator, which translates capacitive changes into a variable-frequency pulse train. An in-depth analysis of the oscillator behavior including all parasitic elements has been performed, and the use of a Schmitt trigger at the inverter chain is proposed to assure oscillation for capacitance values ranging from 1 to 1500 pF. The oscillation frequency is estimated by using a 16-b counter and the appropriate user-defined counting interval ranging from a few microseconds to several seconds in order to achieve maximum accuracy within the entire capacitance range. The 2-B word thus produced can be sent to a host computer through a serial or parallel interface for further processing. To demonstrate the concept, a 16-channel interface has been described in a hardware description language and implemented on a complex programmable logic device. Measurement of two different capacitive pressure sensors developed in-house reveals frequency sensitivity values of -252.1 and -9.54 Hz/fF, which are in good agreement with the expected values derived by the analytic relations. View full abstract»

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  • Polynomial Chirplet Transform With Application to Instantaneous Frequency Estimation

    Publication Year: 2011 , Page(s): 3222 - 3229
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (977 KB) |  | HTML iconHTML  

    In this paper, a new time-frequency analysis method known as the polynomial chirplet transform (PCT) is developed by extending the conventional chirplet transform (CT). By using a polynomial function instead of the linear chirp kernel in the CT, the PCT can produce a time-frequency distribution with excellent concentration for a wide range of signals with a continuous instantaneous frequency (IF). In addition, an effective IF estimation algorithm is proposed based on the PCT, and the effectiveness of this algorithm is validated by applying it to estimate the IF of a signal with a nonlinear chirp component and seriously contaminated by a Gaussian noise and a vibration signal collected from a rotor test rig. View full abstract»

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  • Digital Stochastic Measurement of a Nonstationary Signal With an Example of EEG Signal Measurement

    Publication Year: 2011 , Page(s): 3230 - 3232
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (227 KB) |  | HTML iconHTML  

    This paper presents a method of digital stochastic measurement (DSM) of nonstationary signals. The method is based on stochastic analog-to-digital (A/D) conversion and accumulation, with a hardware structure based on a field-programmable gate array and a low-resolution A/D converter. The characteristic of previous implementations of DSM was the measurement of stationary signal harmonics. This paper shows how DSM can be extended and also used when it is necessary to measure the time series of nonstationary signals. An electroencephalography signal is selected as an example of a real nonstationary signal, and its DSM is tested by simulations and experiments. Tests are done without adding noise and with adding a noise-varying signal-to-noise ratio (SNR) from 10 to -10 dB. The results of simulations and experiments are compared versus theory calculations, and the comparison confirms the theory. The presented method provides control of the measurement uncertainty even at low SNR values, by controlling the sample rate of the used A/D converter. This enables designers of measurement systems to choose fast A/D converters with low resolution to achieve higher measurement accuracy. View full abstract»

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  • CMOS Voltage-to-Frequency Converter With Temperature Drift Compensation

    Publication Year: 2011 , Page(s): 3232 - 3234
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (261 KB) |  | HTML iconHTML  

    This paper presents a new complementary metal-oxide-semiconductor (CMOS) differential voltage-to-frequency converter (VFC) suitable for sensor signal conditioning. Designed in a low-cost 0.18- μm CMOS process, the proposed VFC consumes less than 0.4 mW at a 1.8-V supply. For a differential input range of 0-1.2 V, output frequency varies from 0.1 to 1.1 MHz with a linearity error of less than 0.4%. A new temperature compensation technique keeps the gain error below 2.4% over the whole frequency span for a range of -20°C- +120°C. View full abstract»

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Aims & Scope

Papers are sought that address innovative solutions to the development and use of electrical and electronic instruments and equipment to measure, monitor and/or record physical phenomena for the purpose of advancing measurement science, methods, functionality and applications.

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