Dissertationen zum Thema „Faible consommation d'énergie“
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Dumont, Éric. „Étude d'une maison à faible consommation d'énergie : Habitasol 2000“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ26567.pdf.
Der volle Inhalt der QuellePoulain, David. „Dimensionnement des réseaux métropolitains transparents à faible consommation d'énergie“. Versailles-St Quentin en Yvelines, 2013. http://www.theses.fr/2013VERS0012.
Der volle Inhalt der QuelleIn this thesis we address the problem of dimensionning metropolitan all-optical rings with low energy consumption. A new architecture for all-optical nodes, called Packet Optical Add-Drop Multiplexer (POADM), improves the performance of metropolitan networks while reducing their energy consumption and therefore their operating costs. A POADM is composed of advanced optical receivers whose unit cost is elevated. The number of these equipments is variable in each node and it determines the performance but also the capital expenditure of the network. We offer design solutions to both ensure network performance while minimizing the cost of deploying it
Hannachi-Belkadi, Nazila Kahina. „Développement d'une méthodologie d'assistance au commissionnement des bâtiments à faible consommation d'énergie“. Phd thesis, Université Paris-Est, 2008. http://tel.archives-ouvertes.fr/tel-00468589.
Der volle Inhalt der QuelleAmador, Erick. „Décodeurs LDPC à faible consommation énergétique“. Phd thesis, Télécom ParisTech, 2011. http://pastel.archives-ouvertes.fr/pastel-00599316.
Der volle Inhalt der QuelleFranciscatto, Bruno. „Conception et réalisation d'un nouveau transpondeur DSRC à faible consommation“. Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENT037/document.
Der volle Inhalt der QuelleTo increase the efficiency and safety of the road traffic, new concepts and technologies have been developed in Europe since 1992 for RTTT applications (Road Traffic & Transport Telematics). These applications use the Dedicated Short Range Communications (DSRC) devices at 5.8 GHz (ISM band). In view of the reliability and success of this technology, the use of such equipment is thus extended to the EFC (Electronic Fee Collection) or e-toll and also in many other application areas such as fleet management, public transport and parking management. Due to the broad applications, these equipments are subject to various standards CEN/TC 278, CEN ENV (EN) 12253, ETSI, etc.... The DSRC system consists in a transceiver (reader) and transponders (tags). Industrial approaches are oriented to semi-passive transponder technology, which uses the same signal sent by the reader to retransmit, performing a frequency shift and encoding data to be transmitted. This design avoids the use of the local oscillators to generate the RF wave, as in active transponders, and save electrical energy of batteries. This allows the development of relatively low cost and small size transponders. Despite advances in integrated low-power circuits technology, this concept still requires a lithium battery to operate the transponder for a period of 4-6 years. However, with the expansion of these facilities, it appears that over the years the amount of lithium to destroy has become a crucial problem for the environment. Nowadays designing a completely autonomous DSRC transponder is not feasible, since the amount of energy required is still high (8 mA/3.6 V active mode). Nevertheless, reducing the transponder electrical power consumption, as a solution to at least double the battery life, could be a good start point to improve environment protection.In this thesis we propose a new DSRC transponder with an original statechart that considerably reduces the power consumption. After validation of the new low-power consumption mode, we studied the possibility to recharge the battery of the transponder by means of Wireless Energy Harvesting. The DSRC Toll Collection RF link budget was carried out in order to estimate the amount of energy available when a car with a transponder passes through a toll system. However, RF link budget at 5.8 GHz presents a low power density, since the car does not stay enough on the DSRC antenna's field to proceed to energy harvesting. Therefore we explored another ISM frequency, the 2.45 GHz. Thus the Wireless Energy Harvesting chapter aims to further the state of the art through the design and optimization of a novel RF harvesting board design. We demonstrated that an optimum RF-DC load is required in order to achieve high RF-DC conversion efficiency. Several rectifiers and rectennas were prototyped in order to validate the numerical studies. Finally, the results obtained in this thesis are in the forefront of the State-of-the-Art of Wireless Energy Harvesting for very low available power density
Harari, Stéphanie. „Contrôle modal semi-actif et actif à faible consommation énergétique par composants piézoélectriques“. Phd thesis, INSA de Lyon, 2009. http://tel.archives-ouvertes.fr/tel-00443734.
Der volle Inhalt der QuelleDurand, Sylvain. „Commande faible coût pour une réduction de la consommation d'énergie dans les systèmes électroniques embarqués“. Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00586620.
Der volle Inhalt der QuelleSlimani, Kamel. „Une méthodologie de conception de circuits asynchrones à faible consommation d'énergie : application au microprocesseur MIPS“. Grenoble INPG, 2004. https://tel.archives-ouvertes.fr/tel-00008328.
Der volle Inhalt der QuelleTo increase the autonomy of embedded systems such as portable phones or computers, several researches on integrated circuit design have been performed in order to reduce the energy consumption. This Phd work aims at proposing to the designer the means to design low energy digital integrated circuits. Three important steps have been proposed in this work to reduce the energy consumption of circuits. The first step is to use asynchronous logic to design circuit. Indeed, several works achieved these last years have shown that asynchronous logic can significantly reduce the energy consumption of circuits. The second step is to offer tools that allow the designer to get information on the activity and the energy consumption of a circuit during the design flow. An activity estimator and an energy estimator have been specified that allow the designer to get relevant information on the distribution of the activity and the energy within a circuit during a specific simulation. Finally, optimisation techniques have been defined to reduce the energy consumption of circuits. The estimation methodology and the energy consumption optimisation techniques have been applied to the implementation of a processor. The results have shown an energy consumption reduction of 24%
Saddi, Zied. „Conception d'un dispositif de récupération d'énergie mixte vibratoire-électromagnétique pour l'alimentation des dispositifs à faible consommation“. Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1065/document.
Der volle Inhalt der QuelleEnergy harvesting is an attractive solution to power supply low-power electronics and wireless communication devices avoiding the use of power sources like batteries which have a limited life, requires periodic replacements and have a cost of recycling. Among the available ambient energy sources, electromagnetic waves and mechanical vibrations are the most suitable because of their availability particularly in the urban areas. Our contribution focuses on the study and implementation of a vibrational energy harvesting device using the electrostatic transduction. This system, based on a capacitance modulation, requires a voltage pre-charge given by an auxiliary source. To avoid electret or piezoelectric materials characterized by a limited lifetime, the initialization step was provided by a rectenna (Rectifying antenna).A new structure of dual-band rectenna (2.45 GHz and 1.8 GHz) based on a hybrid ring has been proposed. It allows to increase the received RF power but also to simplify the matching circuit. It experimentally achieves 320 mV voltage and 40 % efficiency when the power densities are 1.13 and 1.87 mW/cm2 at 1.85 and 2.45 GHz, respectively. A Cockcroft-Walton voltage multiplier rectenna was also designed and experimentally characterized. A voltage of 1.06 V was measured at a power density of 1.55 mW/cm².A macro-scale electrostatic vibration harvester (e-VEH), wirelessly pre-charged with a 2.45 GHz Cockcroft-Walton rectenna, was studied, designed and experimentally characterized. The e-VEH uses the Bennet doubler as conditioning circuit. A voltage of 23 V across the transducer terminal has been measured when the vibration harvester is excited at 25 Hz and 1,5g of external acceleration. An energy of 275 µJ and a maximum power of 0.4 µW are available across the load. A lumped element model of the electrostatic transducer has been proposed. Based on mechanical/electrical equivalent equations, an equivalent electrical circuit is derived using the LTspice simulator to study the behavior of the system and provide the voltage and the power converted.Keywords: Energy harvesting, rectenna, microstrip antenna, RF-to-dc converter, electrostatic transduction, Bennet’s doubler, modélization
Ordas, Sébastien. „Évaluation de méthodes faible consommation contre les attaques matérielles“. Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS023/document.
Der volle Inhalt der QuelleThe consumption of integrated circuits has been increasing over the last decade. With the increase of energy prices and the democratization of embedded systems, methods to manage the consumption performance compromise, such as the dynamic management of the frequency and the supply voltage or the substrate potential, were developed. These methods, which are becoming more commonly implemented in integrated systems, allow to reduce the consumption of those latter, and to better manage the tradeoff between consumption and performance.Some of these circuits, embedding these methods, may have to perform some operations with confidential information. It is therefore necessary to consider the possible impact of these methods on the safety of the integrated systems. In this context, the work reported in this thesis aimed to analyze the compatibility of these methods of power management with the design of robust circuits to physical attacks.Specifically, the objective was to determine whether these low-power techniques constitute real obstacles or facilitate the attacks by observation or perturbation exploiting the electromagnetic channel. Initially, a study on the effectiveness of attacks by observation in the presence of random management of voltage, frequency and substrate polarization was done. Secondly, the impact of the dynamic management of supply voltages and substrate polarization on the ability to inject faults by electromagnetic medium was studied. This document presents the overall results of these analyzes. Keyword : Hardware Attacks, Side Channel Attacks, Faults Attacks, Electromagnetic canal, DVFS, Body-biasing
Chefi, Ahmed. „Conception d'un micro capteur d'image CMOS à faible consommation d'énergie pour les réseaux de capteurs sans fil“. Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENT003/document.
Der volle Inhalt der QuelleThis research aims to develop a vision system with low energy consumption for Wireless Sensor Networks (WSNs). The imager in question must meet the specific requirements of multimedia applications for Wireless Vision Sensor Networks. Indeed, a multimedia application requires intensive computation at the node and a considerable number of packets to be exchanged through the transceiver, and therefore consumes a lot of energy. An obvious solution to reduce the amount of transmitted data is to compress the images before sending them over WSN nodes. However, the severe constraints of nodes make ineffective in practice the implementation of standard compression algorithms (JPEG, JPEG2000, MJPEG, MPEG, H264, etc.). Desired vision system must integrate image compression techniques that are both effective and with low-complexity. Particular attention should be taken into consideration in order to best satisfy the compromise "Energy Consumption - Quality of Service (QoS)"
Ali, Muhammad. „Stockage de données codées et allocation de tâches pour les centres de données à faible consommation d'énergie“. Electronic Thesis or Diss., CY Cergy Paris Université, 2023. http://www.theses.fr/2023CYUN1243.
Der volle Inhalt der QuelleData centers are responsible for a significant portion of global energy consumption. This consumption is expected to grow in the coming years, driven by the increasing demand for data center services. Therefore, the need for energy-efficient, low-carbon data center operations is growing rapidly.This research focuses on designing and implementing a low-carbon, energy-efficient data center powered by solar and hydrogen, granting it independence from the power grid. As a result, the data center is limited by the upper bound on the energy consumption, which is 10KWh. The maximum usage of energy-constraint imposes several challenges to the design, energy usage, and sustainability of the data center.The work first contributes to designing a low-power budget data center while respecting the overall energy constraint. We tried to save the energy usage of the data center through the right choice of hardware while keeping the performance of the data center intact. The second contribution of our work provides valuable protocols like lazy repair in distributed data storage, job placement, and power management techniques to further reduce the data center's energy usage. With the combined efforts of the right choice of hardware, protocols, and techniques, we significantly reduced the overall energy consumption of the data center
Verrascina, Nicola. „Design of ULP circuits for Harvesting applications“. Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0115/document.
Der volle Inhalt der QuelleIn the modern devices Ultra-low power consumption is thesurvival key for the energy-harvested sensor node. The reduction of thepower budget can be achieved by mixing different low–power techniquesat three levels of abstraction: transistor level, circuit level and systemlevel. This thesis deals with the analysis and the design of Ultra-LowPower (ULP) circuits suitable for Energy-Harvesting Wireless SensorNetworks (EHWSN). In particular, voltage regulator and RF transmissioncircuits are examined. The former is the main block in powermanagement unit; it interfaces the transducer circuit with the rest of thesensor node. The latter is the most energy hungry block and thusdecreasing its power consumption can drastically increases the sensoron-time
Dessales, Denis. „Conception d'un réseau de capteurs sans fil, faible consommation, dédié au diagnostic in-situ des performances des bâtiments en exploitation“. Poitiers, 2011. http://nuxeo.edel.univ-poitiers.fr/nuxeo/site/esupversions/db809f07-98d1-49ad-b9e8-b8633225fabc.
Der volle Inhalt der QuelleThis PhD thesis is the result of a collaborative research through a CIFRE agreement between the XLIM-SIC laboratory at the University of Poitiers and the Scientific and Technical Center Building (CSTB) at Grenoble. The main goal of this thesis concerns the design and the energy optimization of a wireless sensor network able to measure during several years, the building energy performances (lighting, acoustics, temperature. . . ). To this end, research was mainly focused on the energy optimization of radio communications, through the lower layers of the OSI model. Because the physical layer performances directly impact the efficiency of the other layers, the approach was to model realistically the digital transmission chain from the development of a channel model which takes into account the people moving on the transmission quality. Then, from this physical layer model and an existing energy model, the quality of radio links has been evaluated in order to find the best trade-off between the robustness and the energy efficiency of radio transmissions. To extend our reasoning to a network scale, the following work has focused on the MAC layer study. Because of the interdependence of the parameters affecting consumption, the method chosen was to assess with a "cross-layer" approach, the energy performances of different MAC protocols, by taking into account the impact of the physical layer performances in the assessment. This study then resulted in the definition of an efficient MAC protocol for the aimed application. The final part of the work was devoted to the experimental design of a demonstrator operating on 433 and 868 MHz ISM bands, and allowed us to validate the theory developed during the thesis
Lùcio, de Sales Damas Pedro Alberto. „Effet Pockels dans les guides d'onde en silicium contraint : Vers la modulation optique à haute vitesse et faible consommation d'énergie dans le silicium“. Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS178/document.
Der volle Inhalt der QuelleThis work is devoted to the study of second order nonlinearities in silicon towards low power, high speed modulation. Being a centro-symmetric crystal, silicon does not possess a second order nonlinear susceptibility (X2), which inhibits Pockels effect, a linear electro-optic effect commonly used in the modulation of light in high speed communications. A possible solution to overcome this limitation is by straining/deforming the crystal lattice, which locally breaks the centro-symmetry of the crystal and generates X2.In this thesis, we approach the problem of generating X2 in silicon through the use of strain, covering all the research stages: we depart from newly developed theoretical grounds, simulate together the strain, optical and electrical effects together, describe the fabrication of the devices and present the experimental characterization.In our research work, we were able to detect very particular effects which are attributed to Pockels effect, such as a clear dependence of the crystal orientation on the modulation efficiency and high speed modulation, at frequencies higher than those expected from other contributions. This results are very promising and consist on a step further towards the possible implementation of high speed, low power modulation in silicon devices in the near future
Salazar, Gutierrez Camilo Andrés. „Récepteurs de réveil très faible consommation utilisant des techniques de filtrage de type N-Path“. Thesis, Lille 1, 2015. http://www.theses.fr/2015LIL10031/document.
Der volle Inhalt der QuelleThe continuous development of performant systems intended for Wireless Sensor Networks (WSN) sets an exciting motivation to bring “intelligence” to our environment. Multiple researches have been addressed to the development of advanced methodologies enabling the possibility of providing objects with individual wireless sensing devices. Set as sensor networks, these emerging WSN enables autonomous monitoring of diverse environments for applications such as medical care, environmental monitoring, system security and smart structures. To guaranty dense node deployment and long lifetime, each sensor node must be small, low-cost and low-power. In order to fulfill the WSN low-energy requirements, asynchronous rendez-vous schemes based on Wake-Up Receivers (WuRx) may be implemented. This thesis research focuses on the development of a compact and low-cost ultra-low power wake-up receiver providing high sensitivity and strong interference rejection. The proposed architecture overcomes the need of high-Q time-base references by combining a low-Q resonator-referred local oscillator and distributed multi-stage signal-path high-Q filtering obtained by means of integrated ULP electronic means. Based on a Dual-IF architecture, this WuRx takes creative advantage of the N-path passive-mixers (N-PPM) impedance frequency translation principle to enhance the sensitivity and provide strong interferer immunity. Implemented in a 65nm CMOS technology from STMicroelectronics, this thesis work pushes the state-of-the-art boundary, proposing a 2.4GHz On-Off Keying (OOK) dual-IF WuRx with -97dBm sensitivity and -27dB carrier-to-interferer ratio at 5MHz carrier frequency offset, while consuming 99μW
Choy, Laurent. „Vers un paradigme de programmation orienté workflow pour la résolution de méthodes d'algèbre linéaire sur des plateformes de calcul global à faible consommation énergétique“. Lille 1, 2007. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/2007/50376-2007-Choy.pdf.
Der volle Inhalt der QuelleKaraoui, Mohamed Lamine. „Système de fichiers scalable pour architectures many-cores à faible empreinte énergétique“. Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066186/document.
Der volle Inhalt der QuelleIn this thesis we study the problems of implementing a UNIX-like scalable file system on a hardware cache coherent NUMA manycore architecture. To this end, we use the TSAR manycore architecture and ALMOS, a UNIX-like operating system.The TSAR architecture presents, from the operating system point of view, three problems to which we offer a set of solutions. One of these problems is specific to the TSAR architecture while the others are common to existing coherent NUMA manycore.The first problem concerns the support of a physical memory that is larger than the virtual memory. This is due to the extended physical address space of TSAR, which is 256 times bigger than the virtual address space. To resolve this problem, we modified the structure of the kernel to decompose it into multiple communicating units.The second problem is the placement strategy to be used on the file system structures. To solve this problem, we implemented a strategy that evenly distributes the data on the different memory banks.The third problem is the synchronization of concurrent accesses to the file system. Our solution to resolve this problem uses multiple mechanisms. In particular, the solution uses an efficient lock-free mechanism that we designed, which synchronizes the accesses between several readers and a single writer.Experimental results show that: (1) structuring the kernel into multiple units does not deteriorate the performance and may even improve them; (2) our set of solutions allow us to give performances that scale better than NetBSD; (3) the placement strategy which distributes evenly the data is the most adapted for manycore architectures
Lenoir, Vincent. „Architectures adaptatives basse consommation pour les communications sans-fil“. Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAT085/document.
Der volle Inhalt der QuelleThis thesis work takes part in the connected objects theme, also known as the Internet of Things (IoT). It emerges from the Internet democratization since the early 2000's and the shift to highly mobile devices, made possible by the miniaturization of embedded systems. In this context, the energy efficiency is mandatory since today's projections are around tens of billions of connected devices in 2020. However for ease of deployment and usage, a large part of the data transfers in these networks is wireless, which implementation represents a significant part of the power consumption. Indeed, the energy efficiency question is addressed in general as a fine tuning of hardware architectures, which is often associated with a favorable technology evolution. Nevertheless, this design paradigm quickly reached its limits since it necessary implies a highly constrained sizing to be compatible with the worst operating conditions, even if they are not effective most of the time. It's typically the case with wireless communications since the radio channel is a medium characterized by a strong variability due to propagations effects and interferences. Thus, our study focused on the design of a communication chain whose link budget can be dynamically tuned depending on the actual signal attenuation, in order to reduce the system power consumption. The thesis has contributed to the design of a self-adaptive receiver dedicated to IEEE 802.15.4 standard, by proposing both a reconfigurable digital baseband architecture and an automatic control method of the operating mode. More precisely, the work relied on two approaches, the compressive sampling and the partial sampling, to reduce the data's size to process, decreasing the internal activity of arithmetics operators. In return, the demodulation processing needs a higher SNR, degrading in the same time the receiver sensitivity and thus the link budget. This solution, implemented in an STMicroelectronics CMOS 65 nm LP process, offers a low hardware overhead compared to conventional architecture with only 23,4 kgates. Thanks to the circuit physical model that has been developed, the power consumption for a packet demodulation is estimated to 278 uW when the baseband is fully activated. It can however be gradually decreased down to 119 uW, corresponding to a sensitivity reduction of 10 dB. Thus, the proposed digital baseband and its control loop save 30 % of energy in average in a typical use case
Vauché, Rémy. „Conception de générateurs d'impulsions ultra-large bande en technologie CMOS“. Thesis, Aix-Marseille 1, 2011. http://www.theses.fr/2011AIX10098.
Der volle Inhalt der QuelleThe information theory developed by Claude Shannon (1916 - 2001) highlights the fact that in order to increase the capacity of a transmission channel, it is preferable to extend the bandwidth used rather than the transmission power. This finding is the starting point of many papers on Ultra-Wideband (UWB) which led to the creation in the United States of UWB band since 2002 where no modulation is privileged. Two years later, many works on Impulsionnal Radio UWB (IR-UWB) communications began at IM2NP including the design of low noise amplifier, power detector, but also pulse generators which is the key element of IR-UWB emitters. These form basis of works presented in the manuscript that took place from 2008 to 2011. The discontinuous nature of communications impulse was first implied the introduction of new figures of merit for measuring performances of pulse generators. Then it deals with design techniques for sizing structures operating at frequencies involved, but also to reduce consumption and especially static leakage to reduce enough power consumption for embedded systems. Finally three architectures of pulse generators are developed, each one responding to different constraints in terms of frequency, consumption and range
Olivier, Aurélien. „Fabrication et caractérisation des transistors à effet de champ de la filière III-V pour applications basse consommation“. Thesis, Lille 1, 2010. http://www.theses.fr/2010LIL10162/document.
Der volle Inhalt der QuelleAn autonomous system is composed of a sensor, a digital controller, a communication interface and an energy source. Its consumption should be less than about 100 microW. To reduce power consumption, new components called the Green transistors have appeared in various topologies, operating modes and alternative materials to silicon. The communication interface consists of a transistor with high performances at low power supply. The topologies used are the high electron mobility transistor (HEMT) and the metal-oxide-semiconductor field-effect transistor (MOSFET) and only III-V-based channels with low bandgap energy, low effective mass and high electron mobility should achieve these goals. Antimonide based HEMTs (AlSb/InAs) and InGaAs MOSFETs technologies have been developed. Measurements of transistors AlSb /InAs HEMTs showed performance above 100GHz at 10mW/mm at room and cryogenic temperatures and transistors which 1mW/mm equals to 10GHz can be expected. However, significant gate currents and a high aspect ratio in a HEMT structure limit the reduction the factor of merit between the power and the cut-off frequency. Thus, the technology of InGaAs MOSFET has been characterized during this work and the RF results are promising (fT = 120GHz, Lg = 200nm) even if the process fabrication is not fully optimized. A perspective of this work is the use of antimonide materials for the realization of ultra low power MOSFET
Haloua, Abderrahmane. „Étude d’un protocole de communication asynchrone faible consommation à lien radio impulsionnel ultra-large bande : implémentation sur silicium des fonctions RF critiques“. Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0255.
Der volle Inhalt der QuelleIn recent years, research has been devoted to the study and development of Wireless Sensor Network (WSN). These research are a response to the increase of the connected objet number in the world with development of smartphones and Internet of things (IoT). Energy consumption in sensor networks is one of the most studied areas. In fact, the optimization of the consumption of the elements making up the sensor networks allows a reduction in the costs associated with their installation, operation and maintenance. Communications in sensor networks represent an important part of their power consumption. In order to reduce the consumption of communications in sensor networks, different levels of optimization are possible. In this context, various IM2NP research projects aimed at reducing transceiver consumption through innovative design were carried out. Much of this work has been devoted to Impulsionnal Radio Ultra-Wide Band (IR-UWB). Moreover, MAC protocols used to manage the communication channel access in wireless sensor networks are also important in optimizing their consumption. The research work proposed in this manuscript, based on the work on impulse radios UWB carried out within the IM2NP, propose an optimization of the consumption of sensor networks on two levels. Firstly, an asynchronous MAC protocol based on radio wake-up radio suitable for UWB communications is proposed as well as its energy study. Following the study of the proposed asynchronous protocol, the design of a low power semi-passive wake-up receiver (WuRx) and a UWB sub-GHz impulse generator is presented and their performance in terms of energy efficiency discussed
Mbarek, Ons. „Une approche de modélisation au niveau système pour la conception et la vérification de systèmes sur puce à faible consommation“. Phd thesis, Université Nice Sophia Antipolis, 2013. http://tel.archives-ouvertes.fr/tel-00837662.
Der volle Inhalt der QuelleSamir, Anass. „Conception de solutions basses puissances et optimisation de la gestion d'énergie de circuits dédiés aux applications mixtes“. Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4700.
Der volle Inhalt der QuelleFor three decades, the market trend answers the current demand of miniaturization and performance increase of the multimedia devices. Yet, any reduction of the dimensions of a given factor imposes a decrease of the tensions (for reasons of reliability). To answer this question, the downsizing of CMOS integrated circuits reaches submicron scales of integration resulting in a significant decrease in the reliability of components and in particular transistors. The hot carriers creations, as well as heat dissipation within the submicron circuits, are the two main physical phenomena behind the reliability decline. The technical solution to maintain a good degree of reliability, while reducing component size, is to reduce the supply voltage of circuits. In parallel to performance constraints, environmental standards require consumption as small as possible. The challenge is then to build circuits combining low power supply (voltage and current) where the concept of circuits "Low Power". These circuits are used for some already in the field of multimedia, medical, integration with various constraints (possibility of external components, stability, etc..). The speed increase performance of digital circuits also requires the use of technologies that generate leaks increasingly important that are inconsistent with consumption reduction in standby modes without the introduction of new techniques
Verdant, Arnaud. „Architectures adaptatives de traitement des images dans le plan focal“. Paris 11, 2008. http://www.theses.fr/2008PA112361.
Der volle Inhalt der QuelleImage sensors are an integral part of our daily lives. These deviees are most commonly implemented in mobile products for which remain strong constraints of energy consumption. Indeed, the images captured by such sensors contain many spatial and time redundancies when considering a video stream. Many data are unnecessarily processed, transmitted and stored, thereby inducing a lack of autonomy in such systems. The thesis work carried out aimed to address this power constraint by defining new architectural approaches to image processing within the matrix of pixels, to adapt sensor resources based on the activity of the observed scene. Thus, new concepts of acquisition and processing related to motion detection have been studied. The processing architecture, derived from subsequently developed algorithms, while offering solutions to ensure the integrity of the analog data. Original modelling methodology was finally implemented in order to validate the proposed concepts, to ensure the processing consistency, robustness and induced consumption. Finally, a demonstrator was designed to validate the silicon implementation of the architecture. The power consumption gains are estimated from 30 to 700 compared to the image sensor sensors state of the art
Al, Khatib Chadi. „Conception de dispositifs de contrôle asynchrones et distribués pour la gestion de l’énergie“. Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAT016/document.
Der volle Inhalt der QuelleToday integrated systems are increasingly faced with the constraints of low consumption or energy efficiency. These issues need to be integrated as far upstream as possible in the design flow to reduce design time and avoid much iteration in the flow. In this context, the collaborative project HiCool, between LIRMM and TIMA laboratories, Defacto, Docea and ST Microelectronics companies, has set up a strategy and design flow to design integrated low power systems while facilitating the reuse of existing hardware blocks (IPs). The approach proposed in this thesis fits into this strategy by bringing a small dose of asynchrony in completely synchronous systems. Indeed, the reduction in consumption is based on the observation that permanent activation of the entire circuit is unnecessary in many cases. However, controlling the activity with techniques of "clock gating" or "power gating" usually need to perform a re-design of the system and to add a control device for controlling activation of areas effecting treatment. The work presented in this manuscript provides a strategy based clock controllers and power domain, asynchronous, distributed and easily insertable into a circuit with a low cost design
Camus, Manuel. „Architecture de réception RF très faible coût et très faible puissance : application aux réseaux de capteurs et au standard ZigBee“. Phd thesis, Université Paul Sabatier - Toulouse III, 2008. http://tel.archives-ouvertes.fr/tel-00309926.
Der volle Inhalt der QuelleDusch, Yannick. „Nano-Système Magnéto-Électro-Mécanique (NMEMS) ultra-basse consommation pour le traitement et le stockage de l'information“. Phd thesis, Ecole Centrale de Lille, 2011. http://tel.archives-ouvertes.fr/tel-00697174.
Der volle Inhalt der QuelleBedier, Mohammed. „Circuits d’interface intégrés sur silicium pour une gestion optimale de la puissance dans les récupérateurs d’énergie vibratoire à transduction capacitive“. Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066376/document.
Der volle Inhalt der QuelleVibrational energy is an attractive power source for self-powered wireless sensors. A mainstream harvesting technique for vibrational energy is electrostatic MEMS harvesters. Various circuit architectures have already been introduced with many successful implementation, yet a load interface that efficiently manages the harvested energy has rarely been reported. In this work a load interface is proposed which is suited for any condition circuit (CC) implementing rectangular QV cycles. In general, a rectangular QV conditioning circuit has an optimum interval of which the energy harvested is maximised, thus the harvested energy should be periodically removed to maintain maximising the harvested energy. This is achieved through the load interface (LI). The LI proposed is a switched inductor capacitive architecture with a LI controller allowing the extraction of the energy in a multiple energy shot fashion. The LI controller incorporate an ultra low power clock for switching events and low power comparator for switching decision. Power consumption is reduced by operating at a low supply voltage (1.1V). The LI is implemented in AMS0.35HV technology with a mixed high voltage-low power control blocks. It takes into account the harvester operation to maximise its extracted energy. It overcomes the constrained limited biasing power, tackles resistive losses and power handling transistor long channels by transferring the energy in a multiple shots fashion. A CMOS implementation is proposed along with simulation results showing an average consumed power of the controller less than 100nW allowing the system to operate with input power levels as low as few hundreds of nano-watts
Courdouan, Elie. „Développement d'un module BMS multi-sources harvesting“. Electronic Thesis or Diss., Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0633.
Der volle Inhalt der QuelleWith the development of mobile applications, such as telecoms, IoT and home automation, embedded systems have shown an exponential growth over the past years. The main characteristic of these newly build systems is to combine high processing capabilities and extended operational autonomy. Unfortunately, these parameters are fundamentally opposed and hardware designer facing this issue by limiting processing capability to ensure enough autonomy. To solve this autonomy problem, newly architectures choose to implement an energy harvesting stage with one or more sources. As part of this industrial thesis, the study has been carried out on the design of an optimized energy harvesting module using one or more sources. Two directions were found to increase the quantity of harvested energy: - Interfacing multiple harvester from complementary source in an industrialized architecture - Optimization of produced energy from each source by using next-generation algorithms of Maximum Power Point Tracking. These algorithms are optimized thanks to technical advances made in the field of Deep Learning and the availability of more efficient low power microcontroller. The final goal of this study is to deploy a low cost wide area network of sensors with enhanced or infinite autonomy
Hossain, Mohaimenul. „Green Metrics to Improve Sustainable Networking“. Electronic Thesis or Diss., Université de Lorraine, 2019. http://www.theses.fr/2019LORR0201.
Der volle Inhalt der QuelleAchieving energy efficiency has in recent times become a major concern of networking research due to the ever-escalating power consumption and CO2 emissions produced by large data networks. This problem is becoming more and more challenging because of the drastic traffic increase in the last few years and it is expected to be increased even more in the coming years. Using efficient energy-aware strategies that could overturn this situation by reducing the electricity consumption as well as mitigating the environmental impact of data transmission networks. However, CO2 and energy consumption cannot be considered proportionate if the means of electricity production differs. This research work focuses on reducing the environmental impact of data transmission network by implementing energy aware routing, where unused network devices will be put into sleep/shut down and high capacity links will be adapted according to demand requirement. But, alongside with energy, this work has introduced two different metrics namely carbon emission factor and non-renewable energy usage percentage, which are considered as objective functions for designing green network. Here a centralized approach like using Software-Defined Networking (SDN), is used for designing to solve this problem as they allow flexible programmability suitable for this problem. Our proposal proposes a routing technique using genetic algorithm that minimizes the number of network-elements required and at the same time adapt the bandwidth capacity while satisfying an incoming traffic load. Different from existing related works, we focus on optimizing not only energy consumption but also carbon emission and non-renewable energy consumption in SDN in order to close this important gap in the literature and provide solutions compatible with operational backbone networks. Complementing the general aim of improving the environmental impact of data transmission network, this research is also intended to cover important related features such as realistic large demand size, network performance, and Quality of Service (QoS) requirements. At the same time this work focuses on network stability and analyzes the impact of network stability while implementing a green solution. Our work proposes a penalty and filtering mechanism which helps to find an optimal balance between stability and green networking. By using realistic input data, significant values of switched-off links and nodes are reached which demonstrate the effectiveness of our algorithm. The obtained result validated the importance of considering environmental factors rather than considering only energy. Results also show the trade-off between environmental and performance concerns, considering a couple of performance indicators. Moreover, it is shown that the penalty and filtering mechanism is an effective approach to avoid incoherent system and improve the stability of the system. As a whole, this conducted research and contributions reported through this manuscript stand as a valuable solution on the road to sustainable networking
Saligane, Mehdi. „Adaptive body biasing system for margins reduction using delay and temperature monitoring at near threshold operation“. Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4716.
Der volle Inhalt der QuelleIoT applications continue to push towards ultra-low-power constrained ASICs, creating severe challenges to achieve sufficient power efficiency in extreme Voltage and Temperature conditions. Thus, it is necessary to build closed-loop compensation systems that are autonomous to environmental conditions especially temperature at sub-threshold regime. Two major work are proposed: an adaptive techniques that allow to enhance the performance of designs that leverage aggressive voltage scaling. we fully exploits the FD-SOI 28nm technology dual gate capabilities to both attain optimal power efficiency points and compensate for gradual changes in overall device performance due to process, voltage, and temperature variations. Our proposed compensation Unit system is a fully-digital error-prediction solution providing a compromise between industry reliability requirements and manufacturing guard-band reduction with low-invasiveness and post-silicon tunability. Critical-Paths timing monitors are distributed across the processor and tuned to match the closest critical paths. A programmable workload emulator allows to adapt and take into account the processor tasks. Generated warning Flags due to V-T variations are analyzed based on an adjustable warning rate and body bias is adapted correspondingly. Based on the operation voltage, either fine or coarse body biasing can be activated for compensation. The second part of this thesis addresses on-chip temperature monitoring that plagues aggressively voltage scaled ASICs. We propose to closely monitor temperature fluctuations at low-voltage but also hot-spot detection at nominal and over-drive supply voltage conditions
AYADI, Ahmed. „L'efficacité énergétique des protocoles de transport fiables pour les réseaux sans fil à faible consommation d'énergie“. Phd thesis, 2012. http://tel.archives-ouvertes.fr/tel-00741994.
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