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Flavia GRASSI Sergio A. PIGNARI
In this paper, multiconductor transmission line (MTL) modelling is used to characterize the frequency response and dispersion of the low-voltage outdoor powerline channel. The analysis focuses on a single transmitter-to-receiver link and all the possible connection schemes associated with that link. By resorting to modal analysis, approximate analytical upper bounds of the channel frequency-response are derived for simplified but representative network configurations involving power cables with star-quad cross-section. Numerical solution of the MTL equations is used to validate the theoretical work and to show the dispersion of the channel frequency-responses, which results to be of the order of 20 dB.
Flavia GRASSI Giordano SPADACINI Sergio A. PIGNARI
In this work, a measurement-based procedure aimed at deriving a behavioral model of Bulk Current Injection (BCI) probes clamped onto multi-wire cable bundles is proposed. The procedure utilizes the measurement data obtained by mounting the probe onto the calibration jig for model-parameters extraction, and 2D electromagnetic simulations to adapt such parameters to the specific characteristics of the cable bundle under analysis. Outcome of the analysis is a behavioral model which can be easily implemented into the SPICE environment. Without loss of generality, the proposed model is here used to predict the radio-frequency noise stressing the terminal units of a two-wire harness. Model accuracy in predicting the common and differential mode voltages induced by BCI at the line terminals is assessed by EM modeling and simulation of the involved injection setup by the commercial software CST Microwave Studio.
Tao LIANG Flavia GRASSI Giordano SPADACINI Sergio Amedeo PIGNARI
This work presents a hybrid formulation of the stochastic reduced order model (SROM) algorithm, which makes use of Gauss quadrature, a key ingredient of the stochastic collocation method, to avoid the cumbersome optimization process required by SROM for optimal extraction of the sample set. With respect to classic SROM algorithms, the proposed formulation allows a significant reduction in computation time and burden as well as a remarkable improvement in the accuracy and convergence rate in the estimation of statistical moments. The method is here applied to a specific case study, that is the prediction of crosstalk in a two-conductor wiring structure with electrical and geometrical parameters not perfectly known. Both univariate and multivariate analyses are carried out, with the final objective being to compare the performance of the two SROM formulations with respected to Monte Carlo simulations.
Flavia GRASSI Giordano SPADACINI Keliang YUAN Sergio A. PIGNARI
In this work, a novel formulation of crosstalk (XT) is developed, in which the perturbation/loading effect that the generator circuit exerts on the passive part of the receptor circuit is elucidated. Practical conditions (i.e., weak coupling and matching/mismatching of the generator circuit) under which this effect can be neglected are then discussed and exploited to develop an alternative radiated susceptibility (RS) test procedure, which resorts to crosstalk to induce at the terminations of a cable harness the same disturbance that would be induced by an external uniform plane-wave field. The proposed procedure, here developed with reference to typical RS setups foreseen by Standards of the aerospace sector, assures equivalence with field coupling without a priori knowledge and/or specific assumptions on the units connected to the terminations of the cable harness. Accuracy of the proposed scheme of equivalence is assessed by virtual experiments carried out in a full-wave simulation environment.
Flavia GRASSI Giordano SPADACINI Sergio A. PIGNARI Filippo MARLIANI
In this work, a computationally-efficient modeling approach is developed to predict the electromagnetic noise induced in the terminal units of random bundles of twisted-wire pairs mounted onboard spacecraft. The proposed model combines the results of a preliminary fullwave simulation, aimed at evaluating the electromagnetic field inside the space vehicle's metallic body, with a stochastic model of a random bundle, based on multiconductor transmission line (MTL) theory. Model assessment versus measurement data obtained characterizing real wiring harness in a full-scale satellite mock-up demonstrates the large sensitivity (up to 40 decibels) of the induced noise levels to different bundle configurations, and corroborates the effectiveness of the proposed simplified modeling strategy for estimating the modal noise voltages induced in the terminal units.