A. Moschitta, D. Petri
This paper investigates the statistical properties of quantization noise. In particular, a theoretical model is discussed, which evaluates the power of quantization noise introduced by a memoryless Analog to Digital Converter (ADC) as a function of both the converted signal distribution and the ADC thresholds positioning. Expressions have also been derived to express the Integral Non-Linearity (INL) contribution to quantization noise power as an additive term, and to evaluate such a term with a simple formula. Simulation results that validate the proposed expression are provided.
XVII IMEKO World Congress
· TC4
· 2003
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E. Nunzi, P. Carbone, D. Petri
Performances of ΔΣ modulators are evaluated by applying a coherently sampled tone and by estimating powers of the in-band tones and noise. In particular, the power of the shaped noise is usually estimated by subtracting the evaluated input tone from the output data and by integrating the power spectral density estimated by means of the periodogram. Although the coherency, the finite number of processed samples induces spectral leaking of the wide. band noise, thus affecting the noise power estimate. To cope with such an issue, usually data are weighted by the Hanning sequence. In this paper,...
XVII IMEKO World Congress
· TC4
· 2003
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F. Stefani, A. Moschitta, D. Macii, D. Petri
An appropriate choice of the computing devices employed in digital signal processing applications requires to characterize and to compare various technologies, so that the best component in terms of cost and performance can be used in a given system design. In this paper, a benchmark strategy is presented to measure the performances of various types of digital signal processing devices. Although different metrics can be used as performance indexes, Fast Fourier Transform (FFT) computation time and Real-Time Bandwidth (RTBW) have proved to be excellent and complete performance parameters....
XVII IMEKO World Congress
· TC4
· 2003
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C. Cherbaucich, G. Crotti, N. Kuljaca, M. Novo
A method for the assessment of the dynamic behaviour of heavy current shunts is described, which is based on the evaluation of the shunt frequency response through spectral analysis of input and output measured signals. The method has been tested by applying it to simulated current impulses and experimented in the case of a pulse current, generated by the discharge of a cable capacitance, measured by a thin walled coaxial-tube shunt.
XVII IMEKO World Congress
· TC4
· 2003
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L. Ferrigno, A. Pietrosanto, A. Celano
The paper deals with the enhancement of a Bluetooth-based interface for instrumentation, which has the aim of satisfying the need of wireless connection today arising in developing automatic measurement systems. The interface improvements are widely described as for both hardware and software components. Finally a complete experimental test set allows conclusions to be drawn about the interface performance.
XVII IMEKO World Congress
· TC4
· 2003
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N.Hlupic, D.Petrinovic, J.Butorac
Time Domain Spectral Analysis is presented in this paper as a new, original approach to the analysis of signal spectrum (having samples of the measured signal). The uniqueness of this method is in avoiding of any kind of Fourier transform, which showed to be of limited accuracy when the samples' errors (measurement imperfections) are taken into account, even applying windows and various approximations. The majority of calculations are based on our previously developed method for high accuracy measurement of a single sine wave. The basic idea of this method is to extract all time domain...
XVII IMEKO World Congress
· TC4
· 2003
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Domenico Mirri, Gaetano Iuculano, Gaetano Pasini, Pier Andrea Traverso, Fabio Filicori
In this paper the conventional equally spaced sampling technique for spectrum analysis is compared to an asynchronous random sampling strategy, which has been previously proposed by authors for other broadband digital instrumentation. To this aim, two new approaches to the performance analysis are exploited, both being characterised by the fact that no classical DFT algorithms are applied. In the first method, the analytical expression for the estimate of signal harmonic components is defined as a direct approximation of the Fourier series coefficients and the parameters that characterise...
XVII IMEKO World Congress
· TC4
· 2003
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Massimo Aiello, Antonio Cataliotti, Valentina Cosentino, Salvatore Nuccio
In the last years the increased interest about power quality, forced international working groups to define new standards for testing and measurement techniques. In this paper a pc-based power quality instrument is proposed, according to IEC 61000-4-7 and standard IEC 61000-4-30. It is a low-cost and easily reconfigurable instrument able to measure harmonics, interharmonics and amplitude disturbances and supply unbalance. The complete instrumentation has been tested using standard test procedures in order to verify its accuracy limits.
XVII IMEKO World Congress
· TC4
· 2003
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Maurizio Caciotta, Michela Cristiani
The problem of perceived electrical power quality by users of the Little Medium Enterprises (LME) is settled and matched with the difficulty to individuate the correct instrumentation that is able make their satisfaction. The exorbitant quantity of instruments that are on the market, that, the builders assure, measure power quality, cannot be completely managed by operators. The paper present a system based on automatic lexical procedure that read the manuals and extract the information that can be properly managed by a Kohonen non supervised neural network to obtain an optimal inner...
XVII IMEKO World Congress
· TC4
· 2003
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Janusz Mindykowski
The present paper deals with the selected problems of electrical energy quality assessment in the power system under non-sinusoidal conditions, i.e. the real power system. The principals are understood by the author as the three-segment block which consists of the basic definitions concerning power quality and its assessment, methods to determine electrical power quality indices by using the appropriate mathematical tools, as well as the related instrumentation for solving a problem of electrical power quality assessment. In the paper, these three fundamental parts for solving the electrical...
XVII IMEKO World Congress
· TC4
· 2003
· Download