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Evaluation of the Impact of Transient Disturbances on Railway Signaling Systems Using an Adapted Time-Frequency Analysis Method

Kousri M. R., Deniau V., Heddebaut M., Baranowski S.

International Journal of Electronics and Telecommunications

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2017

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Vol. 63, No. 4

347--354

EN

As many other industrial environments, the railway electromagnetic environment is characterized by a large number of electromagnetic signals and disturbances. Among these, transient signals, with high energy level and wide frequency spectrum, represent an important threat to different signaling subsystems. In this paper, a new methodology dedicated to the detection and the characterization of the transient disturbances is presented. Based on a flexible and adjustable time-frequency analysis, this methodology is used to evaluate the impact of transient disturbances on a ground-to-train radio communication. A test bench was developed in order to validate the results of this evaluation.

2

Energy Consumption Models For MISO-UWB and TR-MISO-UWB Systems

El Abboubi A., Elbahhar F., Heddebaut M., Elhillali Y.

International Journal of Electronics and Telecommunications

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2017

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Vol. 63, No. 3

285--291

EN

This paper, an energy consumption model is developed and exploited to evaluate the electrical energy consumption of ultra-wideband impulse radio (UWB-IR) systems. We develop the energy consumption models and our comparative study, on the one hand, for a system based single-input singleoutput (SISO) configuration and a multiple-input single-output (MISO) and, on the other hand, for a time reversal TR-MISO configuration and for MISO alone configuration. We consider an indoor propagation environment based on the 802.15.4a channel model. The results show very different behaviors depending on the propagation conditions, the number of antennas used, or on the number of transmitted symbols. Using such a model, a radiofrequency designer can obtain significant inputs to optimally select an adequate configuration to design an adaptive energyaware UWB-IR system.

3

DS-UWB and TH-UWB Energy Consumption Comparison

Elabboubi A., Elbahhar F., Heddebaut M., Elhillali Y.

Journal of Telecommunications and Information Technology

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2016

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nr 1

101--109

EN

The energy consumption of the wireless communication systems is starting to be unaffordable. One way to improve the power consumption is the optimization of the communication techniques used by the communication networks and devices. In order to develop an energy efficient UWB multi-user communication system, the choice of modulation and multi access technique is important. This paper compares two Ultra-wideband multi-user techniques, i.e. the DS-UWB and the TH-UWB in the case of the Nakagami-m fading channel. For the DS-UWB technique, the orthogonal (T-OVSF, ZCD) and non-orthogonal (Kasami) codes are used. For TH-UWB, authors consider different modulations (PPM, PSM, PAM). This comparison allows choosing the best solution in terms of energy consumption, data rate and communication range. Two different studies are realized to find the most efficient technique to use. In the first study, the same number of users for the different type of codes (data rate values) is chosen and the total energy consumption for several distances and path-loss coefficient is computed. In the second one, the multiusers effects (same data rate) for various values of distances and path-loss are evaluated.