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Instrumentation and Measurement, IEEE Transactions on

Issue 9 • Date Sept. 2010

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Displaying Results 1 - 25 of 30
  • Table of contents

    Page(s): C1 - 2249
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  • IEEE Transactions on Instrumentation and Measurement publication information

    Page(s): C2
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  • Distributed Unsupervised Gaussian Mixture Learning for Density Estimation in Sensor Networks

    Page(s): 2250 - 2260
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (671 KB) |  | HTML iconHTML  

    This paper considers the problem of density estimation and clustering in sensor networks. It is assumed that measurements of the sensors can statistically be modeled by a common Gaussian mixture model (GMM). In this paper, a distributed expectation maximization (DEM) algorithm is developed to estimate the model order and the parameters of this model. Scalability and fault tolerance are two important advantages of this method. In the E-step of this algorithm, each node calculates local sufficient statistics using its local observations. A distributed averaging approach is then used to diffuse local sufficient statistics to neighboring nodes and estimate global sufficient statistics in each node. In the M-step, each node updates parameters of the GMM using the estimated global sufficient statistics. Diffusion speed and convergence of the proposed algorithm are also studied. The proposed method is then used for environmental monitoring and also distributed target classification. Simulation results approve the promising performance of this algorithm. View full abstract»

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  • Experimental Investigation of Ultrasound Wave Focusing in Attenuative Solids

    Page(s): 2261 - 2271
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    This paper presents an experimental study on ultrasonic focusing in an attenuative solid made of cement mortar. The objective is to comparatively investigate the performance of various techniques for wave focusing. Standard attenuation measurements are performed on small cement mortar samples to generate a preliminary idea about the loss in the material. Subsequently, focusing experiments are conducted on a larger mortar block fabricated with the same mix design parameters. The time-delayed and time-reversal methods are employed to perform focusing. A synthetic aperture approach is used to generate the unfocused and focused fields. The time-reversal focusing method generates a narrower focal spot in comparison to the time-delayed method, indicating better focusing action. The experimental results are also compared with an analytical model of focusing in an attenuative fluid with an array of point sources, and a good agreement is confirmed. View full abstract»

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  • Impact of Decorrelation Techniques on Sampling Noise in Radio-Frequency Applications

    Page(s): 2272 - 2279
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (808 KB) |  | HTML iconHTML  

    Analog-to-digital converter (ADC) noise limits the dynamic range of many radio-frequency systems for test and measurement, sensor, and communications applications. Improvements in the total dynamic range (as measured by the SNR) can be achieved by combining M ADCs in parallel, yielding an increase in SNR of M if the noise is fully uncorrelated across ADC units. However, the presence of correlated noise will limit the SNR improvement to a factor less than M. Noise in an ADC is due to thermal processes, quantization, and clock jitter. In an array of ADCs, thermal and quantization noise are independently generated in each ADC, but if a common clock is used, its jitter will generate correlated sampling noise in all the ADCs in the array. In this paper, we analyze and experimentally measure the impact of previously proposed harmonic decorrelation techniques on the sampling noise of an array of parallel ADCs driven by a common clock, sampling at an intermediate frequency. Both theory and experiments reveal that the decorrelation techniques reduce the total sampling noise by half, which is a result that could substantially relax clock requirements for high-dynamic-range systems and thus reduce clock costs. View full abstract»

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  • A Spatially Selective Correlative Filtration Method Based on the Multiscale Edge Shift-Correlative Technique

    Page(s): 2280 - 2285
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    In terms of signal denoising, filtering out high-frequency noise while effectively preserving the useful high-frequency information is a hot topic for research. In this paper, we propose a wavelet modulus maxima spatially selective correlative filtration (SSCF) algorithm to filter out the high-frequency noise mixed in the useful signals. The proposed algorithm is different from traditional noise filtration algorithms in that it need not estimate noise and is not easily affected by noise. The SSCF algorithm first searches the modulus maxima from the multiscale wavelet coefficients of the signal and analyzes the corresponding edge information. Then, it identifies the noise components and useful components from the edge information. For noise components, the algorithm smoothes them away. For useful edge information, the algorithm aligns the corresponding modulus maxima in the wavenumber domain using the shift-related technique. This process amends the “drift” phenomenon of modulus maxima across scales. Next, the proposed algorithm multiplies the aligned multiscale wavelet coefficients that can strengthen the useful signal and attenuate the noise information. We apply the proposed SSCF algorithm to denoise the infrared absorption spectrum of electric insulation gas SF6. Experiments show that the proposed scheme can effectively suppress noise and, at the same time, preserving the useful components. View full abstract»

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  • Modulation Quality Measurement in WiMAX Systems Through a Fully Digital Signal Processing Approach

    Page(s): 2286 - 2302
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    The performance assessment of worldwide interoperability for microwave access (WiMAX) systems is dealt with. A fully digital signal processing approach for modulation quality measurement is proposed, which is particularly addressed to transmitters based on orthogonal frequency-division multiplexing (OFDM) modulation. WiMAX technology deployment is rapidly increasing. To aid researchers, manufactures, and technicians in designing, realizing, and installing devices and apparatuses, some measurement solutions are already available, and new ones are being released on the market. All of them are arranged to complement an ad hoc digital signal processing software with an existing specialized measurement instrument such as a real-time spectrum analyzer or a vector signal analyzer. Furthermore, they strictly rely on a preliminary analog downconversion of the radio-frequency input signal, which is a basic front-end function provided by the cited instruments, to suitably digitize and digitally process the acquired samples. In the same way as the aforementioned solutions, the proposed approach takes advantage of existing instruments, but different from them, it provides for a direct digitization of the radio-frequency input signal. No downconversion is needed, and the use of general-purpose measurement hardware such as digital scopes or data acquisition systems is thus possible. A proper digital signal processing algorithm, which was designed and implemented by the authors, then demodulates the digitized signal, extracts the desired measurement information from its baseband components, and assesses its modulation quality. The results of several experiments conducted on laboratory WiMAX signals show the effectiveness and reliability of the approach with respect to the major competitive solutions; its superior performance in special physical-layer conditions is also highlighted. View full abstract»

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  • An Open-Source Scaled Automobile Platform for Fault-Tolerant Electronic Stability Control

    Page(s): 2303 - 2314
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    Today's technology allows the construction of complex experimental apparatus with reasonable budget. This paper supplies detailed guidelines for constructing a low-cost scaled automobile platform for research and education in vehicle dynamics and control. It summarizes the knowledge gathered when designing, building, and evaluating a model car, which was deployed in a real-world environment for testing an electronic stability control (ESC) algorithm. The model car was built using off-the-shelf hardware and open-source software. Data from a variety of onboard sensors are fused in real time so as to deliver accurate measurements to the ESC algorithm, whereas sensor fault diagnosis is achieved at the same time through an innovative approach based on artificial neural networks (NNs). The detailed presentation of this case study provides a roadmap on how a researcher can build effective experimental automotive platforms for research and educational purposes. View full abstract»

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  • Active Noise Cancellation Without Secondary Path Identification by Using an Adaptive Genetic Algorithm

    Page(s): 2315 - 2327
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3027 KB) |  | HTML iconHTML  

    This paper presents an adaptive genetic algorithm (AGA) for an active noise control (ANC) system. The conventional ANC system often implements the filtered extended least mean square (FXLMS) algorithm to update the coefficients of the linear finite-impulse response (FIR) and nonlinear Volterra filters, owing to its simplicity; meanwhile, the FXLMS algorithm may converge to local minima. In this paper, the FXLMS algorithm is replaced with an AGA to prevent the local minima problem. Additionally, the proposed AGA method does not require identifying the secondary path for the ANC, explaining why no plant measurement is necessary when designing an AGA-based ANC system. Simulation results demonstrate that the effectiveness of the proposed AGA method can suppress the nonlinear noise interference under several situations without clearly identifying the secondary path. View full abstract»

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  • Gaussian Jitter-Induced Bias of Sine Wave Amplitude Estimation Using Three-Parameter Sine Fitting

    Page(s): 2328 - 2333
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (403 KB) |  | HTML iconHTML  

    In this paper, the bias on the estimated amplitude, which is caused by Gaussian jitter, is studied in case of the IEEE 1057 standard three-parameter sine-fitting method. Because no analytical study exists, this source of uncertainty is usually not considered. Nowadays, it is becoming more and more important due to the ever increasing sampling rates available in analog-to-digital converters (ADCs), which are used in innumerable application like high-speed digital oscilloscopes. The effect of additive noise is also taken into account. View full abstract»

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  • A Fully Integrated Built-In Self-Test \Sigma {-}\Delta ADC Based on the Modified Controlled Sine-Wave Fitting Procedure

    Page(s): 2334 - 2344
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1047 KB) |  | HTML iconHTML  

    This paper demonstrates the first fully integrated built-in self-test (BIST) Σ-Δ analog-to-digital converter (ADC) chip to the best of our knowledge. The ADC under test (AUT) comprises a second-order design-for-digital-testability Σ-Δ modulator and a decimation filter. The purely digital BIST circuitry conducts single-tone tests for the signal-to-noise-and-distortion ratio (SNDR), the dynamic range, the offset, and the gain error of the AUT. The BIST design is based on the proposed modified controlled sine-wave fitting procedure to address the component overload issues, reduce the setup parameter numbers, and eliminate the need for parallel multipliers. The total gate count of the whole BIST circuitry is only 13 300. The hardware overhead is much less than the BIST design using the traditional fast Fourier transform (FFT) analysis. Measurement results show that the peak SNDR results of the proposed BIST design and the conventional FFT analysis are 75.5 and 75.3 dB, respectively. The subtle SNDR difference is already within analog test uncertainty. The BIST Σ-Δ ADC achieves a digital test bandwidth higher than 17 kHz, very close to the rated 20-kHz bandwidth of the AUT. View full abstract»

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  • A Knowledge-Based Approach to Online Fault Diagnosis of FET Biosensors

    Page(s): 2345 - 2364
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2438 KB) |  | HTML iconHTML  

    Real-time diagnosis of insulator-semiconductor field-effect transistor (ISFET)-based biosensor systems aims at promptly correcting errors caused by insufficient function; insufficiency is judged by the operational behavior of the sensor, i.e., the data that it produces. Ultimately, a complete failure of the system (i.e., a “dead” sensor) should easily be recognized. Much more difficult is the recognition of a gradual malfunction of this complex system, which may be attributed to faults or failures in one or more of its subsystems. Evidently, the identification of the possible fault modes and their symptoms requires in-depth knowledge of sensor's design and operation, both from the biochemical and electrical/electronic points of view, along with tackling uncertain, incomplete, or imprecise information. In this paper, a novel real-time diagnostic expert scheme for field-effect transistor (FET)-based biosensing is proposed. This paper 1) investigates the causes of sensor misfunction by means of fault tree analysis (FTA) relying on fuzzy reasoning to account for uncertainty and 2) proposes a computer-aided method for diagnosing biosensor failure during operation through an algorithmic procedure that is based on a nested loop mechanism. The tree (dendritic) structure (built using the information provided by the biosensor components and their intrarelations/interrelations on a surface- and a deep-knowledge level) serves as the knowledge base (KB), and the fuzzy-rules-based decision mechanism is the inference engine for fault detection and isolation. View full abstract»

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  • Imaging Systems and Algorithms for the Numerical Characterization of Three-Dimensional Shapes of Granular Particles

    Page(s): 2365 - 2375
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2481 KB) |  | HTML iconHTML  

    The shear properties of natural granular particles such as sand are significantly dependent on the shapes of the particles in the mixture. This is important from a practical viewpoint, because a measurement and characterization technique for the 3-D shapes of such particles can lead to an improved understanding of soil stability and influence the design of structural foundations. Previous techniques that have been developed for this purpose have proven to be complex, and the associated instrumentation has proven to be expensive. Furthermore, conventional 2-D shape measurement and description methods do not readily lend themselves to parsimonious 3-D representations. The situation is further complicated by the fact that, to parameterize the relationship between shape and shear characteristics, a single numerical descriptor is required to model the 3-D shapes of multiple particles in a natural sand particle mixture. This paper describes an optical tomography technique for the measurement of particle data that is then characterized using statistical 3-D shape descriptors. The algebraic reconstruction technique (ART) is used to synthesize 3-D particle shapes from 2-D tomography projections. It is shown that the measurement and characterization techniques used can provide distinct features for differently shaped particle mixtures and can be used to synthesize 3-D composite particles representative of the entire mix. The novelty of the technique described in this paper is that numerical shape descriptors can be obtained for not only a single 3-D object but also an entire collection of 3-D objects. Furthermore, the statistical nature of the 3-D shape descriptor of a particle mixture can be used to synthesize a mixture containing an arbitrary number of particles that have similar but not identical shapes. Results demonstrating the efficacy of the method on a set of natural sand particle mixtures are presented. View full abstract»

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  • Determination of High-Frequency d - and q -axis Inductances for Surface-Mounted Permanent-Magnet Synchronous Machines

    Page(s): 2376 - 2382
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (381 KB) |  | HTML iconHTML  

    This paper presents a reliable method for the experimental determination of high-frequency d- and q -axis inductances for surface-mounted permanent-magnet synchronous machines (SMPMSMs). Knowledge of the high-frequency d- and q-axis inductances plays an important role in the efficient design of sensorless controllers using high-frequency signal injection techniques. The proposed method employs a static locked-rotor test using an ac +dc power supply. By injecting a high-frequency rotating voltage vector into the machine, the d- and q-axis inductances may simultaneously be determined with no need to change the rotor position. Measurements are carried out at steady state. The recording of instantaneous waveforms using a dedicated data acquisition system is avoided. In this paper, experimental results are presented, on a commercial SMPMSM, using the proposed method. View full abstract»

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  • Automatic Detection and Surface Measurements of Micronucleus by a Computer Vision Approach

    Page(s): 2383 - 2390
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    This paper reports a novel method for nucleus and micronucleus segmentation. These biological structures are useful to biologists for relieving structural chromosome aberration. The adopted method consists of a pipeline of advanced computer vision algorithms, some of them were specifically tailored for the current segmentation problem. Starting from the weak hypotheses on size, shape, and color of micronucleus, it is possible to efficiently segment and measure the image features of interest by a computer vision approach. We report experimental results with a new flow cytometer architecture specifically developed to recognize and measure micronucleus of human lymphocyte. The robustness of the algorithm with respect to various kinds of noise is also reported. View full abstract»

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  • Instruments and Methods for Calibration of Oscillometric Blood Pressure Measurement Devices

    Page(s): 2391 - 2404
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    Most of automatic blood pressure measurement devices on the market implement an oscillometric method. This paper highlights the need for standardized calibration procedures for these devices in order to reduce logistical difficulties, time-consuming processes, and high costs involved in clinical validations. A critical overview of researchers' and manufacturers' proposals to answer this need is presented as a contribution to the IEEE P1721 project for a new standard on Objective Measurement of Systemic Arterial Blood Pressure in Humans. View full abstract»

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  • Utilization of Target Scattering to Measure High-Level Electromagnetic Fields: The MICHELSON Method

    Page(s): 2405 - 2413
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    The intention of this paper is to present the instantaneous electromagnetic field measurement by signature of a neutral object (MICHELSON) method. The MICHELSON method is relatively new and enables the measurement of high-level electromagnetic fields from the utilization of a target. The incident field scattering on the target allows us to move the field measurement to a new location where the scattered field can then be measured using simple equipment and without breakdown risk. This method does away with the necessity for cables in the test zone. When using small targets, the induced disturbances in the incident field are limited. The MICHELSON method is implemented to characterize high-level electromagnetic sources whereby the signals radiated can be harmonic signals as well as transient pulses. View full abstract»

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  • An Efficient TIS Measurement Technique Based on RSSI for Wireless Mobile Stations

    Page(s): 2414 - 2419
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (558 KB) |  | HTML iconHTML  

    A technique for using a receive signal strength indicator to measure the total isotropic sensitivity of a wireless handset is proposed in this paper. This technique separates the measurements of the mobile station radiated sensitivity and its receive antenna gain. A single measurement of the mobile station radiated sensitivity is performed while the mobile station antenna gain is obtained through the receive signal strength indicator. Hence, a significant reduction in measurement time can be achieved. The fundamental theory for the method is described. Techniques for reducing the ±2 dB error in the receive signal strength indicator reporting system and the improvement of the measurement resolution are developed. Overall, this technique can reduce measurement time by a significant factor and also improve measurement accuracy over the conventional measurement approach. View full abstract»

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  • Wireless LXI Bus Clock Synchronization and Triggering Design

    Page(s): 2420 - 2430
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (969 KB) |  | HTML iconHTML  

    In this paper, a wireless local area network (WLAN) extension for instrumentation (LXI) [WLXI] bus combining the technology of WLAN and LXI bus is proposed. Several different kinds of methods are designed to implement clock synchronization and triggering. For clock synchronization, a method using the IEEE 1588 protocol based on extended Kalman filter (EKF) is introduced as emphasis. For this method, the wireless IEEE 1588 protocol is used as a communication protocol of clock synchronization, and EKF is used to resolve the clock's nonlinear shifting. The EKF improves the precision of clock synchronization, thus, high-precision clock synchronization for WLXI is realized. For triggering, a method based on the direct-sequence (DS) ultrawideband (UWB) is introduced and emphasized. For this method, DS spread-spectrum (DSSS) UWB is used as a modulation mode, combined with “lagging delay” wireless triggering to realize high-precision synchronization triggering for WLXI. View full abstract»

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  • Broadband 20- \Omega 20-W Load Suitable for Characterization of Switch-Mode Amplifiers

    Page(s): 2431 - 2436
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    This paper reports on a broadband dc ground isolated 20-Ω absorber for powers of up to 20 W. The realized absorber achieves reflections (referenced to 20 Ω) below -10 dB over almost two frequency decades from less than 50 MHz to 2 GHz. It can be used as load resistor in the characterization of power amplifiers, particularly switch-mode ones, where broadband non-50-Ω loads are required for measurement purposes. An additional advantage is that no bias-T is needed with this solution. This reduces measurement uncertainties due to the parasitics of the bias-T. Using the distributed concept offers a generic technique to realize such loads and also for other impedance values and other applications. View full abstract»

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  • Compact Gaussian Beam System for S-Parameter Characterization of Planar Structures at Millimeter-Wave Frequencies

    Page(s): 2437 - 2444
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1054 KB) |  | HTML iconHTML  

    This paper describes the design and implementation of a compact quasi-optical Gaussian beam system for measuring the frequency response of millimeter-wave materials, frequency-selective surfaces, and antenna elements in the array environment. The core components of this system are two wideband millimeter-wave focusing array antennas that act as adapters between the coaxial ports of the network analyzer and the wave ports defined at the input and output planes of the device under test. The use of planar focusing arrays for generating the Gaussian beams leads to very compact measurement setups with a total length of only a few centimeters. This paper addresses the design of the Ka/Q-band focusing arrays and demonstrates the utility of the proposed system through experiment. A useful method that allows reproducing two-port S-parameters from one-port measurements will also be introduced. View full abstract»

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  • Modification of the Maxwell–Wien Bridge for Accurate Measurement of a Process Variable by an Inductive Transducer

    Page(s): 2445 - 2449
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (616 KB) |  | HTML iconHTML  

    The small inductance of an inductive transducer generally linearly changes with a process variable, but their measurement by the usual inductive bridge circuit like the Maxwell bridge, the Maxwell-Wien Bridge, the Hay bridge, etc., suffers from errors due to the effect of the stray capacitance between bridge nodal points and the ground and the stray inductance on the inductive coil, respectively. The conventional Wagner-Earth technique is not suitable for continuous measurement. In this paper, a modified operational-amplifier-based Maxwell-Wien bridge measurement technique has been proposed in which the effect of stray capacitance and inductance is minimized. In the first phase of the experiment, the bridge performance has been studied with a known variable inductor, and in the second phase, the same experimentation was done by replacing the variable inductor with an inductive coil having an adjustable core position for the measurement of displacement. The linear characteristics over a wide range of displacement with good repeatability, linearity, and variable sensitivity have been described. View full abstract»

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  • Wireless Readout of Passive LC Sensors

    Page(s): 2450 - 2457
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (663 KB) |  | HTML iconHTML  

    This paper reports simple yet precise equations for automated wireless measurement of the resonance frequency, Q-factor, and coupling coefficient of inductively coupled passive resonant LC circuits. This allows remote sensing of all physical and chemical quantities that can be measured with capacitance transducers. Formerly reported front-end circuit concepts for wireless sensor readout, i.e., phase dip measurement and the dip meter, are subsequently discussed. It is shown that, due to fundamental system limitations, the formerly reported circuit concepts are not applicable if the distance between the sensor and the readout electronic circuit becomes too small, resulting in large coupling coefficients. Therefore, we present an improved concept for an analog front-end circuit of the readout system that overcomes these limitations and hence allows wireless sensor readout under a wider range of operating distances. View full abstract»

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  • Performance Characteristics of a MEMS Quadrupole Mass Filter With Square Electrodes: Experimental and Simulated Results

    Page(s): 2458 - 2467
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1038 KB) |  | HTML iconHTML  

    Size reduction in quadrupole mass spectrometers (QMSs) is an ongoing requirement driven by the needs of space exploration, portable, and covert monitoring applications. Microelectromechanical systems (MEMS) technology provides a method of achieving this size reduction. A quadrupole mass filter (QMF) is one component of a QMS and is suitable for microfabrication. MEMS manufacturing techniques are more suitable to the production of rectilinear electrodes, instead of the more widely used circular electrodes. Present understanding of the performance characteristics of rectilinear electrodes and the dependence of these characteristics on electrode geometry are not well documented. In this paper, we report on the performance characteristics of a square-electrode QMF. Both the predicted performances obtained by computer simulation and experimental data are presented for operation in stability zone 1 (0.236, 0.706) and zone 3 (3.16, 3.23). A comparison between these results and the simulated data for equivalent devices constructed using hyperbolic and circular electrodes for operation in zone 1 is also made. This comparison demonstrates that, although the field produced by square electrodes is far from the “ideal,” it is still possible to achieve useful filtering action. Our results also show that, for operation in zone 3, performance comparable with that of hyperbolic and circular electrodes operating in zone 1 is achievable. View full abstract»

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  • Nonlinear Induced Variance of Frequency Response Function Measurements

    Page(s): 2468 - 2474
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    This paper analyzes the variance of the estimated frequency response function (FRF) ĜBLA of the best linear approximation ĜBLA to a nonlinear system that is driven by random excitations. ĜBLA varies not only due to the disturbing measurement and process noise but also over different realizations of the random excitation because the nonlinear distortions depend on the input realization. It will be shown that the variance expression σBLA2 that is obtained in the linear framework can also be used to calculate the variance that is induced by the nonlinear distortions. This validates the common engineering practice, where the linear FRF methodology is often used under nonlinear conditions. 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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Meet Our Editors

Editor-in-Chief
Prof. Alessandro Ferrero
Dipartimento di Elettrotecnica
Piazza Leonardo da Vinci 32
Politecnico di Milano
Milano 20133 Italy
alessandro.ferrero@polimi.it
Phone: 39-02-2399-3751
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