By Topic

Instrumentation and Measurement, IEEE Transactions on

Issue 4 • Date Aug. 2006

Filter Results

Displaying Results 1 - 25 of 58
  • Table of contents

    Page(s): c1 - 1022
    Save to Project icon | Request Permissions | PDF file iconPDF (53 KB)  
    Freely Available from IEEE
  • IEEE Transactions on Instrumentation and Measurement publication information

    Page(s): c2
    Save to Project icon | Request Permissions | PDF file iconPDF (47 KB)  
    Freely Available from IEEE
  • Full text access may be available. Click article title to sign in or learn about subscription options.
  • Security monitoring using microphone arrays and audio classification

    Page(s): 1025 - 1032
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (757 KB)  

    In the paper, the authors propose a security monitoring system that can detect and classify the location and nature of different sounds within a room. This system is reliable and robust even in the presence of reverberation and in low signal-to-noise (SNR) environments. We describe a novel algorithm for audio classification, which, first, classifies an audio segment as speech or nonspeech and, second, classifies nonspeech audio segments into a particular audio type. To classify an audio segment as speech or nonspeech, this algorithm divides the audio segment into frames, estimates the presence of pitch in each frame, and calculates a pitch ratio (PR) parameter; it is this PR parameter that is used to discriminate speech audio segments from nonspeech audio segments. The discerning threshold for the PR parameter is adaptive to accommodate different environments. A time-delayed neural network is employed to further classify nonspeech audio segments into an audio type. The performance of this novel audio classification algorithm is evaluated using a library of audio segments. This library includes both speech segments and nonspeech segments, such as windows breaking and footsteps. Evaluation is performed under different SNR environments, both with and without reverberation. Using 0.4-s audio segments, the proposed algorithm can achieve an average classification accuracy of 94.5% for the reverberant library and 95.1% for the nonreverberant library View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • High-resolution absorption coefficient and refractive index spectra of carbon monoxide gas at millimeter and submillimeter wavelengths

    Page(s): 1033 - 1037
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (188 KB)  

    The use of dispersive Fourier transform techniques in interferometry allows the measurement of absorption coefficient and refractive index spectra with great precision. This paper presents the absorption coefficient and refractive index spectra of carbon monoxide (CO) gas at millimeter and submillimeter wavelengths. To assess rotational lines of CO, the gas was measured at four different pressures, giving insight into the behavior of the spectral lines with varying parameters. The measurements in this study demonstrate that varying the pressure of the gas affects only the amplitude of the absorption lines and not their exact position. This is critical in air pollution studies when trying to single out a specific gas from a field sample with unknown constituents View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Agencies for perception in environmental monitoring

    Page(s): 1038 - 1050
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1136 KB)  

    This paper presents the main results obtained in the Agencies for PErception in environmental monitoring (APE) Project, funded by the Italian Ministry of University and Research, and aimed at studying the employment of advanced distributed artificial intelligence techniques in developing cooperative multiagent systems oriented to support environmental monitoring applications. In particular, this paper describes issues about communication between perceptive agents and two implemented multiagent systems for monitoring electromagnetic fields and for pollutant evaluation. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Power measurement in digital wireless communication systems through parametric spectral estimation

    Page(s): 1051 - 1058
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (576 KB)  

    Power measurement in digital wireless communication systems often suffers from poor repeatability, usually accompanied by a low accuracy. To face the problem, the use of parametric spectral estimators is investigated in this paper. In particular, a new method is proposed, which first estimates the power spectral density (PSD) of the analyzed signal through Burg's solution, and then evaluates the power by applying straightforward measurement algorithms to the estimated PSD. The results of a number of experiments, carried out on both laboratory and actual signals peculiar to digital wireless communication systems, assess the efficacy and reliability of the method. Moreover, a comparison of the achieved performance to that offered by an alternative measurement solution, already proposed by the authors and based on nonparametric PSD estimation, shows that the method allows for a significant reduction of measurement time, while exhibiting the same repeatability. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • New proposal for uncertainty evaluation in indirect measurements

    Page(s): 1059 - 1064
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (424 KB)  

    This paper deals with the uncertainty evaluation in indirect measurements. The attention is mainly paid to measurement models whose input quantities are modeled as correlated random variates. Moving from a past proposal related to the use of the unscented transform to overcome key limitations of current guide to the expression of uncertainty in measurement recommendations in the presence of the input quantities modeled as uncorrelated random variates, the authors are going to present a new proposal capable of extending the advantages of the cited transform when correlated input random variates are also concerned. The new proposal is, in particular, addressed to nonlinear and/or nonanalytical measurement models. After describing the key features and implementation issues of the proposal, the results obtained in a number of tests on simulated and actual measurement data are given, which assess its reliability and effectiveness. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Measurement of processing and queuing delays introduced by an open-source router in a single-hop network

    Page(s): 1065 - 1076
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (552 KB)  

    Measurement of the main contributions to the single-hop delay introduced by an open-source router is dealt with. A new method is proposed, which is capable of distinguishing the time interval during which a generic packet stays in either input or output queue (queuing delay) of the router under analysis and the time interval characterizing the effective routing process (processing delay) the packet undergoes. Thanks to proper measurement probes, i.e., kernel-layer functions, the method makes the occurring time of events of interest available at the application layer, thus giving the possibility of separately evaluating the aforementioned delays and, ultimately, pursuing a deeper insight of the considered router. After brief remarks concerning various delays a packet experiences when passing through a generic router, the measurement principle underlying the method is presented in detail. Particular emphasis is put on its capability of locally monitoring the transit of each packet from the input to the output port of an open-source router along with main features and implementation issues of the proposed measurement probes. Results obtained in many experiments carried out on a suitable test bed in different operating conditions are then given in order to highlight the method's reliability and effectiveness. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Ultrasonic time-of-flight estimation through unscented Kalman filter

    Page(s): 1077 - 1084
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (896 KB)  

    This paper deals with distance or level measurements based on ultrasonic time-of-fight estimation. Moving from a past experience concerning the proposal of a method based on discrete extended Kalman filter (DEKF) to overcome some limitations of already available ultrasonic-based techniques, a new digital signal processing method capable of granting further improvements is presented. The method is based on the unscented Kalman filter (UKF), which is a new extension of the Kalman filter theory mandated to face some DEKF problems, mainly due to its inherent linearization approach. To this aim, UKF is applied to the acquired ultrasonic signal in order to estimate the returned echo envelope as well as to locate its onset more accurately. After describing key features and implementation issues of the new method, the results obtained in a number of tests on simulated and actual ultrasonic signals, which assess its reliability and effectiveness as well as advantages with respect to the previous one, are given. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • New results on electromagnetic imaging based on the inversion of synthetic and measured scattered-field data

    Page(s): 1085 - 1093
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (432 KB)  

    A new approach for the inversion of synthetic and measured scattered data is proposed in this paper. The approach is based on an iterative technique in which the nonlinear equations of the inverse-scattering problem are solved within the pth-order Born approximation. A regularization scheme based on an inexact-Newton method is applied. Several numerical simulations and experimental results are reported. Multiple separated dielectric cylinders are localized and reconstructed in a noisy environment. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Phase-plane-derived distortion modeling of a fast and accurate digitizing sampler

    Page(s): 1094 - 1100
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (583 KB)  

    Continued efforts to model the distortion behavior of custom-designed digitizing samplers for accurate measurement of dynamic signals are reported. This work is part of ongoing efforts at the National Institute of Standards and Technology (NIST) to advance the state of the art in waveform sampling metrology. In this paper, an analytic error model for a sampler having a -3-dB 6-GHz bandwidth is described. The model is derived from examination of the sampler's error behavior in the phase plane. The model takes as inputs the per-sample estimates of signal amplitude, first derivative, and second derivative, where the derivatives are with respect to time. The model's analytic form consists of polynomials in these terms, which are chosen from consideration of the voltage dependence of the digitizer input capacitance and the previously studied error behavior in a predecessor digitizer. At 1 GHz, an improvement in total harmonic distortion from -32 to -46 dB is obtained when model-generated sample corrections are applied to the waveform. The effect of timebase distortion in the sampling system is also accounted for and corrected. The inclusion of second-derivative dependence in the model is shown to improve the model's fit to the measured data by providing fine temporal adjustment of the fitted waveform View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Displacement measurements using a self-mixing laser diode under moderate feedback

    Page(s): 1101 - 1105
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (299 KB)  

    A semiconductor laser subject to moderate optical feedback has been used to design an interferometric displacement sensor. The autoadaptative signal processing presented in this paper has been computed in order to improve the accuracy of such a sensor. This setup has been successfully tested for both harmonic and aleatory displacements of a remote piezoelectric actuator with a maximum accuracy of 40 nm View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Space compactor design in VLSI circuits based on graph theoretic concepts

    Page(s): 1106 - 1118
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (473 KB)  

    The realization of a space-efficient support hardware for built-in self-testing (BIST) is of immense significance in the synthesis of very large scale integration (VLSI) circuits. This paper presents a new zero-aliasing compaction approach of test data outputs with an application specifically targeted to digital embedded cores-based system-on-chips (SOCs), which facilitates the design of such space-efficient BIST support hardware. The suggested technique takes advantage of some well-known concepts of conventional switching theory, together with those of strong and weak compatibilities of response data outputs in the selection of specific gates for merger of an arbitrary but optimal number of output bit streams from the module under test (MUT), based on optimal generalized sequence mergeability, as developed and applied by the authors in earlier works. This is novel in the sense that zero aliasing is realized without any modification of the MUT, while a maximal compaction is achieved in almost all cases in reasonable time utilizing some simple heuristics. The method is illustrated with design details of space compactors for ISCAS 85 combinational benchmark circuits using simulation programs ATALANTA, FSIM, and COMPACTEST, confirming the usefulness of the approach for its simplicity, resulting low area overhead, and full fault coverage for single stuck-line faults, thereby making it suitable in a VLSI design environment. With advances in computational resources in the future, the heuristics adopted in the design algorithm may be further improved upon to significantly lower the simulation CPU time and storage View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A photonic crystal fiber sensor for pressure measurements

    Page(s): 1119 - 1123
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (225 KB)  

    The pressure sensitivity of two photonic crystal fibers (PCFs) was measured. A PCF pressure sensor was then successfully developed with PCF PM-1550-01. The measurement results of the pressure sensor at three different temperatures are presented, and in the working region the maximum deviation is within 1% of the dynamic range of the sensor View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Estimating time-series models from irregularly spaced data

    Page(s): 1124 - 1131
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (195 KB)  

    Maximum-likelihood estimation of the parameters of a continuous-time model for irregularly sampled data is very sensitive to initial conditions. Simulations may converge to a good solution if the true parameters are used as starting values for the nonlinear search of the minimum of the negative log likelihood. From realizable starting values, the convergence to a continuous-time model with an accurate spectrum is rare if more than three parameters have to be estimated. A discrete-time spectral estimator that applies a new algorithm for automatic equidistant missing-data analysis to irregularly spaced data is introduced. This requires equidistant resampling of the data. A slotted nearest neighbor (NN) resampling method replaces a true irregular observation time instant by the nearest equidistant resampling time point if and only if the distance to the true time is within half the slot width. It will be shown that this new resampling algorithm with the slotting principle has favorable properties over existing schemes such as NN resampling. A further improvement is obtained by using a slot width that is only a fraction of the resampling time View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Robust positioning technique in low-cost DR/GPS for land navigation

    Page(s): 1132 - 1142
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1335 KB)  

    This paper describes a dead-reckoning (DR) construction for land navigation and sigma-point-based receding-horizon Kalman finite-impulse response (SPRHKF) filter for DR/GPS integration system. A simple DR construction is adopted to improve the performance of both pure land DR navigation and DR/GPS integration system. In order to overcome the flaws of the extended Kalman filter (EKF), the sigma-point KF (SPKF) is merged with the receding-horizon strategy. This filter has several advantages over the EKF, the SPKF, and the RHKF filter. The advantages include the robustness to the system model uncertainty, the initial estimation error, temporary unknown bias, etc. The computational burden is reduced. Especially, the proposed filter works well even in the case of exiting the unmodeled random walk of the inertial sensors, which can occur in the microelectromechanical systems' inertial sensors by temperature variation. Therefore, the SPRHKF filter can provide the navigation information with good quality in the DR/GPS integration system for land navigation seamlessly View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Enhanced sensitivity cross-correlation method for voltage noise measurements

    Page(s): 1143 - 1147
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (209 KB)  

    Ultralow noise measurements often require the application of signal processing and correction techniques to go beyond the noise performances of front-end amplifiers. In this paper, a new method for the voltage noise measurement is proposed, which allows, at least in principle, the complete elimination of the noise introduced by the amplifiers used for the measurements. This is obtained by resorting to the conventional cross-correlation technique for the elimination of the contribution of the equivalent input voltage noise of the amplifiers and by using a new three-step-measurement procedure that exploits different amplifier-configuration measurements in order to subtract the contribution of the equivalent input current noise of the amplifiers View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Calibration of an integrated robotic multimodal range scanner

    Page(s): 1148 - 1159
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1058 KB)  

    Collecting dense range measurements in uncontrolled environments is a challenging problem, as the quality of the measurements is highly dependent on the lighting conditions and the texture of the target surfaces. This dependence affects the registration and data-fusion processes and, consequently, degrades the accuracy of the surface or occupancy models that are computed from the range measurements. Typical approaches to address this issue have concentrated on improving a specific type of range sensor. On the other hand, the overall quality of the sensing can also be enhanced through the development of a mechanism that combines the various range-sensing technologies to form a multimodal range sensor. The resulting problem of the merging datasets can then be solved in two ways: system calibration of the multimodal sensor or data fitting of all the datasets into a single model, of which the latter is more widely implemented. The lack of multimodal-system calibration approaches is due to their complicated and lengthy nature, where individual calibration procedures must be applied to each subsystem and then applied between the subsystems of the multimodal range sensor. This paper proposes a technique to alleviate the problems encountered in a multimodal-system calibration. Straightforward and generic guidelines for the calibration are defined and applied to an in-house integrated multimodal system built from a laser-range-finder system, two structured-lighting systems, and a stereovision system. The system's intracalibration and intercalibration processes are detailed. Reconstructed renderings of the datasets collected with the calibrated multimodal range sensor, without the use of data fitting, are also presented. From these results, the potential benefits of multimodal calibration over the computationally intensive data-fitting methods and the advantages of merging the subsystem's strengths to complement other subsystem's weaknesses are put in evidence View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Electronic gate detection for cell or particle counting and sizing in liquids: front-end characteristics, flow-dependent gate impedance, and its remediation

    Page(s): 1160 - 1168
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (799 KB)  

    The detection sensitivity and the sizing resolution of electronic gating are inherently limited by fluctuating gate impedance and flow-induced noise. Instabilities of this type, as shown, are due to varying flow patterns of the carrier liquid beyond the gate. Their effects, although largely hidden in dc-operated gating, cause broadening and shift of cell/particle-size distributions under measurement. RF-operated gating, more specifically the demodulation operation, is much more hindered. For an investigation of these effects, a physical model is proposed along with a procedure for the identification of the system parameters. A detector of dedicated concept is used for evaluating the model, and, more specifically, for investigating the impact of configurational and hydrodynamic parameters. Experiments prove that the origin of flow-dependent gate impedance is to be located inside a zone of only a few-micrometer extent at the gate outlet. This is confirmed by the calculated electric field patterns. On such grounds, electrode configurations are proposed that minimize the current density in the zone of hydrodynamic instability and, hence, the flow-induced noise. The same configurations also minimize the impedance of the gate as signal source, facilitating broadband operation, and multifrequency cell impedance measurements View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Radiated immunity tests: reverberation chamber versus anechoic chamber results

    Page(s): 1169 - 1174
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (292 KB)  

    This paper concerns the comparison between reverberation chamber (RC) and anechoic chamber (AC) measurements: In particular, the case of an immunity test is considered. A two-wire transmission line is adopted as a device under test (DUT), and the current induced on the line by the external field is monitored to construct a possible susceptibility profile. Both the averaged current over stirrer rotation and the maximum current are considered to show how robust the RC measurement is against the positioning and the orientation of the DUT inside the chamber. As expected from theory, the maximum value is related to the average one by means of the number of the independent positions of the stirrer. Finally, it is highlighted how in the RC it is possible to lose some worst case situations, related to a particular incident field polarization and incoming direction, and the underestimation of the induced current depends upon the chosen number of stirrer positions View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Continuous digital calibration of pipeline A/D converters

    Page(s): 1175 - 1185
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (525 KB)  

    This paper describes a novel continuous calibration technique for pipeline analog-to-digital converters (ADCs). The new scheme utilizes an existing digital calibration algorithm and extends it to work in real time. The goal is to digitally calibrate the pipeline ADCs in the background without interrupting the normal operation of the converter. The concept behind the digital calibration algorithm is described and simulated using a 1-bit/stage pipeline architecture. Dominant static error mechanisms present in pipeline architectures are identified and discussed. These errors are successfully corrected by the implemented digital calibration algorithm. The calibration scheme is transparent to the overall system performance and is demonstrated using a 14-bit ADC with a 1-bit/stage architecture and 16 identical stages. The first seven stages in the pipeline are calibrated. Continuous calibration is realized using a hardware description language and two extra stages located at the end of the pipeline. The extra stages are only used during the calibration process. Verilog implementations of a stage-and-error-correction logic, as well as a finite state machine to control the calibration process, are presented. The real-time digital calibration technique is verified and successfully demonstrated using the Verilog-XL simulator View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Estimating parameterized scalable models from the best linear approximation of nonlinear systems for accurate high-level simulations

    Page(s): 1186 - 1191
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (368 KB)  

    System designers of communication systems need to compare the simulated behavior of a system with the linear and nonlinear specifications. They need high-level models to perform these simulations fast. The existing high-level models for nonlinear components do not scale smoothly with external parameters like the input power. To overcome this problem, a modeling technique based on the best linear approximation is developed. The parameterized models describe trajectories of the poles and zeros as a function of the input power. The resulting models accurately describe both the linear and nonlinear behavior of the system components. They can easily be implemented in modern simulators. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An Iterative Method to Stabilize a Transfer Function in the s - and z -Domains

    Page(s): 1192 - 1196
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (462 KB)  

    Stability of the identified model is crucial in simulations and prediction applications. This paper proposes a two-step procedure that generates guaranteed stable transfer function (matrix) models from noisy data. It consists of an unconstrained optimal noise removal step followed by a stable approximation of the possible unstable estimate. The proposed method is applicable to continuous-time as well as discrete-time and multivariable systems View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Measurement of the effects of temporal clipping on speech quality

    Page(s): 1197 - 1203
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (415 KB)  

    This paper investigates the effects of temporal clipping on perceived speech quality. Temporal clipping usually results from voice activity detection (VAD), or line echo canceller's nonlinear processor, and the clipped speech portions are replaced by comfort noise. A nonintrusive algorithm is proposed to predict speech quality based on the clipping statistics. Mean opinion score (MOS) is used as a metric for speech quality and is measured by perceptual evaluation of speech quality (PESQ). The impacts of speech frame size and noise spectrum on the algorithm are also investigated. The results show that the proposed algorithm can efficiently predict the speech quality. The correlation coefficient between the prediction and the measurement is about 0.975, and the root mean square error for the prediction is 0.20 MOS. The algorithm can be used as an integral part of a general speech quality assessment scheme in voice over Internet protocol (VoIP) View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.

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.

Full Aims & Scope

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
Fax: 39-02-2399-3703