Lamine Kone

Multiconductor Reduction Technique for Modeling Common-Mode Currents on Cable Bundles at High Frequency for Automotive Applications

This paper presents the fundamentals of the so-called ldquoEquivalent Cable Bundle Methodrdquo 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 ldquolow frequencies.rdquo 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 ldquohigh frequencyrdquo 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.

Extension of the “Equivalent Cable Bundle Method” for Modeling Electromagnetic Emissions of Complex Cable Bundles

This paper presents an extension of the so-called ldquoequivalent cable bundle methodrdquo 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 ldquohigh frequenciesrdquo.

On-body calibration and measurements using personal radiofrequency exposimeters in indoor diffuse and specular environments.

For the first time, response of personal exposimeters (PEMs) is studied under diffuse field exposure in indoor environments. To this aim, both numerical simulations, using finite-difference time-domain method, and calibration measurements were performed in the range of 880-5875 MHz covering 10 frequency bands in Belgium. Two PEMs were mounted on the body of a human male subject and calibrated on-body in an anechoic chamber (non-diffuse) and a reverberation chamber (RC) (diffuse fields). This was motivated by the fact that electromagnetic waves in indoor environments have both specular and diffuse components. Both calibrations show that PEMs underestimate actual incident electromagnetic fields. This can be compensated by using an on-body response. Moreover, it is shown that these responses are different in anechoic chamber and RC. Therefore, it is advised to use an on-body calibration in an RC in future indoor PEM measurements where diffuse fields are present. Using the response averaged over two PEMs reduced measurement uncertainty compared to single PEMs. Following the calibration, measurements in a realistic indoor environment were done for wireless fidelity (WiFi-5G) band. Measured power density values are maximally 8.9 mW/m(2) and 165.8 μW/m(2) on average. These satisfy reference levels issued by the International Commission on Non-Ionizing Radiation Protection in 1998. Power density values obtained by applying on-body calibration in RC are higher than values obtained from no body calibration (only PEMs) and on-body calibration in anechoic room, by factors of 7.55 and 2.21, respectively. Bioelectromagnetics. 37:298-309, 2016.

Dual-Band Elliptical Planar Conductive Polymer Antenna Printed on a Flexible Substrate

In this communication, a fully organic dual-band antenna is presented. It consists of a coplanar waveguide coupled to an elliptical monopole antenna designed on a kapton substrate. This antenna is fabricated from a process, based on the use of a conductive polymer (Polyaniline) doped with multiwall carbon nanotubes, that has been optimized for this application. The flexibility of both kapton substrate and doped conductive polymer gives the antenna the ability to be freely crumpled paving the way to body-worn high data rate communications at microwave frequencies. Applications in wireless networks can also be addressed by using this kind of antennas. In this study, a comparison between the performance of an antenna under bending conditions (using a three-dimensional support) and its uncrumpled version is presented. We evaluate the crumpling effect on the resonant frequency, the bandwidth and the radiation patterns. A good agreement is observed between measurements and simulations data, even when the antenna is crumpled.

Comparison of test methods for the characterization of shielding of board-to-backplane and board-to-cable connectors

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.

The 'Equivalent Cable Bundle Method': an Efficient Multiconductor Reduction Technique to Model Industrial Cable Networks

In automotive electromagnetic (EM) compatibility (EMC), the cable bundle network study is of great importance. Indeed, a cable network links all the electronic equipment interfaces included the critical ones and consequently can be assimilated both to a reception antenna and to an emission antenna at the same time. On the one end, as far as immunity problem is concerned, where an EM perturbation illuminates the car, the cable network acts as a receiving antenna able to induce and propagate interference currents until the electronic equipment interfaces and potentially induce dysfunction or in the worst case destruction of the equipment. At low frequency, the interference signal propagating on the cable network is generally considered as more significant than the direct coupling between the incident field and the equipment. On the other end, as far as emission problem is concerned, the EM field emitted by the cable network may disturb itself the electronic equipments by direct coupling. To avoid these problems, automotive manufacturers have to perform normative tests before selling vehicles. These tests are applied on electronic equipments outside and inside the car first to verify that the equipments are not disturbed by an EM perturbation of given magnitude and second to ensure that the EM emission of each equipment does not exceed a limit value at a given distance. Obviously, these tests are not exhaustive and fully representative of real conditions. For example, in immunity tests, two polarizations (vertical and horizontal polarizations) of the EM perturbation are generally tested in free space conditions. In reality, the EM perturbation due for example to a mobile phone outside the car could happen from any direction of space and be reflected by all the scattering objects located in the close environment of the vehicle (ground, other vehicles, buildings,...). Consequently, the contribution of EM modelling is a great tool for automotive manufacturers in order to proceed to numerical normative, additional and also parametric tests at early stages of the car development on numerical models and for a reasonable cost. Moreover, numerical modelling will reduce the number of prototypes built during the

Feasibility of a High-Bit-Rate Power-Line Communication Between an Inverter and a Motor

In the aerospace domain, more electrical aircraft will have to face a drastic issue in the future, in relation to an increase in the number of wires and connectors, which impact weight and system reliability. A possible solution could be using power-line communications (PLC). In this paper, we focus our attention on the feasibility of communication between a pulsewidth modulation inverter and a motor, using a three-phase cable as a physical support for the data transmission, with a transmitting frequency band extending from 1 to 30 MHz. The required raw bit rate is on the order of 5 to 20 Mbits/s. Noise measurements, in both the time and frequency domains, were performed to extract the main characteristics of the impulsive noise generated by the inverter. Channel transfer functions were measured for an inductive coupling to the motor cable. A software tool simulating the communication link was developed, which is based on recent signal specifications for PLC. Furthermore, noise processing techniques are also proposed, to decrease the impact of the impulsive noise on the received signals. By introducing both the measured transfer functions and noise in the simulation tool, performances of the link, in terms of bit error rate, are presented.

Modeling Methodology of Automotive Electronic Equipment Assessed on a Realistic Subsystem

Conducted disturbances induced into automotive electronic equipment can be predicted in the early design phase by numerical simulation. This supposes a realistic modeling of the cable harness, as well as the electronic equipment. This paper evaluates a modeling method by the results obtained on a realistic automotive subsystem. The latter is composed of two pieces of electronic equipment connected to each other by a cable harness. This test case was performed on printed circuit boards (PCBs) with full or partial ground planes and using a representative sample of harnesses. Simulation results are compared with measurement results using multiple cable harness samples. A good agreement between measurement and simulation can be obtained for PCBs with full ground plane, provided that fringing effects of the electronic components are taken into account in the equipment model.

Analyses et mesures du rayonnement électromagnétique engendré par des communications haut débit transmises sur des lignes d'énergie

RésuméL’usage des lignes d’énergie pour des transmissions de données à haut débit en vue d’applications comme l’accès à Internet ou la domotique, est certes très attractif, mais pose le problème des perturbations électromagnétiques conduites et rayonnées occasionnées par ces nouveaux systèmes. Des risques de brouillage de la réception radio sont surtout pressentis dans la bande de fréquences s’étendant de 1 MHz à 30 MHz allouée aux courants porteurs en ligne (CPL) et qui couvre notamment les ondes décamétriques. Cet article présente une analyse des phénomènes qui sont à l’origine de ces sources de perturbations électromagnétiques. Nous nous intéressons particulièrement à la caractérisation du champ magnétique rayonné, en adoptant une démarche basée sur des concepts physiques simples. Les investigations expérimentales et théoriques sont réalisées sur des lignes d’énergie typiques, de dimensions et de complexité différentes. Une place importante est accordée aux interprétations physiques des résultats de mesure, en recherchant la corrélation entre le champ magnétique mesuré et les courants de mode commun et de mode différentiel qui sont véhiculés par la ligne, ainsi que le lien avec les paramètres géométriques de la ligne et les charges qui y sont connectées. Enfin, nous exposons une approche permettant d’évaluer la puissance d’émission des dispositifs CPL, tout en respectant les exigences de la norme harmonisée EN55022 relative aux perturbations conduites produites par tout équipement connecté au réseau d’énergie.AbstractUse of Power Lines Communication for purpose such as Internet access or in-home applications seems to be a very attractive way, however, the problem of conducted and radiated electromagnetic emissions due to these new systems is quite set. The risk of disturbing the Radio communications is, at all, critical in the so-called Short Waves band, from 1 MHz to 30 MHz, allowed to PLC. This paper is aimed in analysing the phenomena that rise to these radiated electromagnetic emissions. We focus especially the analysis to the characterisation of magnetic field by means of simple physical concepts. The experimental and theoretical investigations involve usual power lines owning different dimension and complexity. A large part of this paper is devoted to physical interpretations of the measurement results, underlining the correlation between the magnetic field emission and the common and differential modes currents driven through the line, as well as the connection with the geometrical parameters of the line and with the connected loads. Finally, we present an approach that allows the assessment of the power deliverable by PLC. devices in accordance with the requirements of the harmonised standard EN55022 dealing with conducted emission on the power network.

Experimental validations of the “equivalent cable bundle method”

This paper deals with the experimental validations performed on a large frequency range (100 MHz – 3 GHz) of a method called “equivalent cable bundle method”. This method creates a “reduced” cable bundle containing a limited number of conductors - each of them called “equivalent conductor” - from a multiconductor cable bundle. The main purpose of the method is to use those reduced cable bundle models in larger 3D models for “high frequency” EM immunity coupling assessment in automotive EMC modeling.