Iñigo Adin

Energy harvesting technologies for low-power electronics

Power consumption is one of the most critical issues when designing low-cost electronic devices, such as sensing nodes in wireless sensor networks. To support their operation, such systems usually contain a battery; however, when the battery has consumed all its energy, the node (e.g. the sensor) must be retrieved and the battery replaced. If the node is located in a remote and non-accessible placement, battery replacement can become an expensive (and even impossible) task. This way, energy harvesting has emerged as a suitable alternative to supply low-power electronic systems, by converting ambient energy into electric power. Scavenged energy can be used to directly supply the circuits, or stored to be used when needed. This paper summarises the power needs of a general wireless sensor node and describes the main principles of most representative energy harvesting technologies. Copyright

A 16-kV HBM RF ESD Protection Codesign for a 1-mW CMOS Direct Conversion Receiver Operating in the 2.4-GHz ISM Band

A decreasing-sized π -model electrostatic discharge (ESD) protection structure is presented and applied to protect against ESD stresses at the RF input pad of an ultra-low power CMOS front-end operating in the 2.4-GHz industrial-scientific-medical band. The proposed ESD protection structure is composed of a pair of ESD devices located near the RF pad, another pair close to the core circuit, and a high-quality integrated inductor connecting these two pairs. This structure can sustain a human body-model ESD level higher than 16 kV and a machine-model ESD level higher than 1 kV without degrading the RF performance of the front-end. A combined on-wafer transmission line pulse and RF test methodology for RF circuits is also presented confirming previous results. The front-end implements a zero-IF receiver. It has been implemented in a standard 2P6M 0.18-μm CMOS process. It exhibits a voltage gain of 24 dB and a single-sideband noise figure of 8.4 dB, which make it suitable for most of the 2.4-GHz wireless short-range communication transceivers. The power consumption is only 1.06 mW from a 1.2-V voltage supply.

Eurobalise-Train communication modelling to assess interferences in railway control signalling systems

The evolution of the railway sector depends, to a great extent, on the deployment of advanced railway signalling systems. These signalling systems are based on communication architectures that must cope with complex electromagnetical environments. This paper is outlined in the context of developing the necessary tools to allow the quick deployment of these signalling systems by contributing to an easier analysis of their behaviour under the effect of electromagnetical interferences. Specifically, this paper presents the modelling of the Eurobalise-train communication flow in a general purpose simulation tool. It is critical to guarantee this communication link since any lack of communication may lead to a stop of the train and availability problems. In order to model precisely this communication link we used real measurements done in a laboratory equipped with elements defined in the suitable subsets. Through the simulation study carried out, we obtained performance indicators of the physical layer such as the received power, SNR and BER. The modelling presented in this paper is a required step to be able to provide quality of service indicators related to perturbed scenarios.

Analysis of the coupling path between transient EM interferences produced by the catenary-pantograph contact and on-board railway communication antennas

An in-depth analysis of the electromagnetic interferences generated by trains requires a better understanding of specific railway interference sources. Interferences due to the losses of contact between catenary and pantograph are among them. This paper presents a modeling methodology proposed to analyze the effect of pantograph arcing on GSM-R antennas located on the train roof. The model was developed using the CST™ microwave studio tool. Comparisons were performed with experimental results to assess the quality of the simulation results. Finally, an analysis was carried out in order to discriminate the couplings between the GSM-R antenna and the different components of the model.

Design for test of a low power multi-standard GPS/GALILEO RF front-end

This contribution deals with the complete design of a multi-standard GPS/GALILEO front-end, from setting the specifications through to the complete characterization of the device. Special focus will be given to the design for test and the characterization of the design, as optimizing the time spent on this improves time-to-market for the product under development. The highly integrated, low power GPS/GALILEO front-end is designed with a low-IF architecture. The front-end exhibits a voltage gain of 103dB with a power consumption of 66mW from a 3V voltage supply and 38mW if the internal dual-gain LNA is switched OFF. The SSB noise figure of 3.7dB which makes it suitable for high sensitivity applications. Te implemented architecture allows 3 different configurations, adding flexibility to its future applications.

On-Board Electromagnetic Interference Field-Test and Evaluation of a Non-electrified Railway Regional Line

In order to assess the performance of the wireless communication systems, a railway line is characterised through the identification of electromagnetic interferences (EMI). The aim of this paper is to show the strategy to identify EMI on field as well as the results obtained. First, the need of the analysis and the objectives of the measurement campaign in a non-electrified Italian Regional Railway line between Caligari and San Gavino are shown. After that, the measurement setup developed for the tests is described. Then, the description of the measurement campaign carried out is exposed. Finally, the measurement results are presented. The results show that the frequency bands of GSM, UMTS and Italian 4G are in the frequency ranges where the highest powered signal (around 800 MHz–900 MHz, 1.8 GHz and 1.9 GHz), on the other hand GPS L1 and Galileo E1frequency band is not impacted by any kind of interference signal.

ETCS's Eurobalise-BTM and Euroloop-LTM Airgap Noise and Interferences Review

Wireless communications interfaces are vulnerable to interferers and noise. The effect of interferers and noise in the system will depend on the robustness of the communication system and the criticality of the system. ETCS European Train Control System is a safety-critical system responsible for the train control and command. There are two ETCS constituents installed on the track with a wireless communication to the train, namely Eurobalises and Euroloops that communicate with Balise Transmission Module BTM and Loop Transmission Module LTM. This paper includes an analysis of the state of the art of noise and interferers and proposes the worst case scenarios to be used in the laboratory to measure the robustness of the systems against noise and interferers.

Wireless Communication Emulator Device and Methodology for the ETCS BTM Subsystem

Currently European Train Control System ETCS rollout is a major concern for train manufacturers and railway infrastructure managers. But available laboratory certification procedures do not completely address all the needs of the system, which leads to long and expensive field-testing. This research work proposes a new tool that reduces the required on-site testing amount. The BTM Wireless Communication Emulator WCE reproduces the potential interferers that can be found in the air-gap of the BTM wireless communication channel. That way, the laboratory testing procedures can emulate the behavior of the wireless channel in a more realistic way. The identification of the potential interferers to be included in the emulator has been done first, and the design and implementation has been carried out afterwards. Finally, the testing and validation of the tool has been completed.

EMC precertification laboratory for railway communication equipment

This paper deals with the definition of an EMC precertification laboratory for communication equipment for railway systems. The main objectives are to show to 5th year telecom engineering students how to build an EMC precertification laboratory based on the applicable standards and introduce them into the tests executions and results interpretation. For that, first, it briefly explains why certification of the electronic equipment is required for these systems. The standards and norms relating to EMC certification and its tests are then presented, and there follows a summary of lab definition and a description of the different kinds of testing. Finally, this work concludes that an in-house laboratory can be defined in order to precertify any communication equipment for the railway industry and therefore it is important for telecom engineering student to have dealt with.

Survey of Environmental Effects in Railway Communications.

In order to identify the different external impairments that could exist in the railway environment. A survey of these effects is presented with the aim of identifying the different phenomena that could affect to the communication channel. On one hand, common effects linked to the signal transmission over a wireless communication channel are analysed. On the other hand, as GSM-R is the current communication technology employed in ERTMS, the disturbances interfering it have been studied. Finally, some solutions to mitigate these effects are listed, in this case, focused in handover solutions.