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This paper presents an extension of the so-called 'Equivalent Cable Bundle Method' for the computation over a large frequency range of the electromagnetic radiation of complex cable bundles. The purpose of the method is to reduce the complexity of the problem by grouping together the conductors according to their terminal load configuration and their excitation to reduce the required computation time for the complete cable bundle modeling. As far as the use of the method on emission problems is concerned, a new five-step procedure is established to define the electrical and geometrical characteristics of the reduced cable bundles. After the description of the adjustments required for the application of the method to emitting cases, some numerical and experimental validations performed on simple cable bundles illustrate the efficiency and the advantages of the method. The research described in this paper is considered as a new step in the study of the modeling of complex cable bundles at 'high frequencies.' Index Terms--Cable bundle, electromagnetic emission, electromagnetic topology, numerical modeling.

Two analytical solutions based on transmission-line theory for the total power radiated by a multiconductor line above a ground plane are proposed. The line is not assumed to be electrically short or close to the ground plane, thus making the proposed model suitable for assessing the emission/immunity of actual transmission lines employed in industrial contexts such as in the automotive domain, railway lines, and power-distribution lines. The model allows an imperfect ground plane to be considered through the complex-image approximation together with propagation losses. Numerical and experimental results are provided as a validation, while an empirical rule to assess the accuracy of the results is proposed. The two expressions aim at allowing fast parametric analysis of radiation during the design phase of the electrical and geometrical configuration of an unshielded multiconductor transmission line. Index Terms--Antenna theory, electromagnetic (EM) radiation, multiconductor transmission lines (MTLs).

In this paper, we address the problem of testing radiated emissions generated by rolling stock, when carried out on actual railway sites, as prescribed by the standard EN 50121. The idea of assessing infrastructure impact on test results is presented here by means of an electromagnetic model of railway sites. In the first part, modeling tools are introduced together with some results from the experimental validation. These tools are then applied to actual railway lines proving the importance of site resonances and the ambiguities in the application of the standard EN 50121 in the industrial domain. After pointing out the main difficulties in the simulation of actual railway sites, we present a feasibility study of an alternative procedure for the modeling of a site, based on magnetic field measurements and the solution of an inverse problem with no a priori information about the test site configuration. Index Terms--Electromagnetic (EM) radiation, inverse problems, multiconductor transmission lines, standards, transportation.

This paper presents the fundamentals of the so-called 'Equivalent Cable Bundle Method' for the calculation over a large frequency range of common-mode currents induced on cable bundles by an electromagnetic (EM) perturbation. In particular, the method aims at overcoming the limitation of the multiconductor transmission line theory (MTLN), which is based on the propagation of the quasi-transverse EM (TEM) mode and efficiently used only at 'low frequencies.' The purpose of the method described here is to reduce the computation time by reducing the complexity of the cable bundle models. After a short presentation of the 'high frequency' coupling problem, first, the theoretical basis of the method, and, second, the numerical and experimental validations performed on prototypal cable bundles, in order to illustrate the efficiency and the advantages of the method, are presented. The method described in this paper is considered as a required first step in order to prepare wider applications on real systems in the near future. Index Terms--Cable bundle, cable harness, electromagnetic topology, numerical modeling.

In this paper, we study the transient response of a multiconductor transmission line, by using the formalism of multiple reflections. This often requires an experimental characterization of the cable bundle that becomes tedious for a large number of conductors. In order to reduce the experimental task, we bring two simplifications: The first one is based on the approximation of totally degenerate modes, the second one on the approximation of semi-degenerate modes. Then, some experiments with real bundles have been achieved to validate these simplifications.

In this paper, we present the work carried out in the SOBITS project executed within the framework of the European Measurement and Testing program. The goal of the project was to compare different methods for characterization of the shielding performance of board-to-backplane and backplane-to-cable connectors used in telecommunication and computer systems. Four measurement methods have been selected. Dedicated test samples have been designed and developed in order to enable the measurement of the shielding characteristics of the connectors under test with all methods. Different shielding configurations were considered, in order to determine the influence of the quality of the shield. Single-ended as well as differential excitations have been considered. Among the test samples, a nonshielded version was designed for each signal/ground configurations. This sample was used as a reference. The definition of the quantities that describe the shielding performance is different for each of the measurement methods. Conversion formulas between these quantities have been formulated. They were verified by measuring a reference device that is easy to measure by all methods. Thus we were able to compare the relative shielding effectiveness of the various shielded board-to-backplane and backplane-to-cable connectors for all four measurement methods. The relative shielding effectiveness of a shielded connector was calculated with respect to the nonshielded version. We also compared the different shielding performance results obtained with each measurement method individually. Index Terms--Connectors, measurement, shielding.