Conception de la gestion de l'alimentation à faible bruit, de petite taille et sur-puce pleinement pour les capteurs à pixels CMOS dans des expériences en physique des hautes énergies

Quelles sont les particules élémentaires et comment l'univers proviennent sont les principales forces motrices de la physique des hautes énergies. Afin de démontrer le modèle standard et découvrez la nouvelle physique, plusieurs détecteurs sont construits pour les expériences en physique des hautes énergies. Capteurs à pixels CMOS offrent un compromis attirant entre la vitesse de lecture, le budget matériel, la tolérance au rayonnement, la consommation d'énergie et la granularité, par rapport aux capteurs à pixels hybrides et des dispositifs à transfert de charge. Ainsi, les CPS sont un bon choix pour détecter les particules chargées dans les détecteurs de vertex et des télescopes de faisceau. La distribution de puissance devient un enjeu important dans les détecteurs à venir, puisque une quantité considérable de capteurs seront installés. Malheureusement, le Independent Powering échoue, comme l'approche traditionnelle. Afin de résoudre les problèmes de distribution de puissance et de fournir des tensions silencieuses, cette thèse se concentre sur la conception de la gestion de l'alimentation à faible bruit, à basse consommation d'énergie, de petite taille et sur-puce pleinement pour les CPS. Les CPS sont d'abord introduits en tirer les exigences de conception de la gestion de l'alimentation. La distribution de puissance dédiées à les CPS est ensuite proposé, dans laquelle la gestion de l'alimentation est utilisée comme seconde étape de conversion de puissance. Deux régulateurs sur-puce pleinement sont proposés pour générer la tension d'alimentation analogique et de la tension d'alimentation de référence requis par l'opération d'échantillonnage double corrélé, respectivement. Deux prototypes ont vérifié ces régulateurs. Ils peuvent répondre aux exigences des CPS. En outre, les techniques de gestion de l'alimentation et de la conception tolérance au rayonnement sont également présentés dans cette thèse.What are the elementary particles and how did the universe originate are the main driving forces in the high energy physics. In order to further demonstrate the standard model and discover new physics, several detectors are built for the high energy physics experiments. CMOS pixel sensors (CPS) can achieve an attractive tradeoff among many performance parameters, such as readout speed, granularity, material budget, power dissipation, radiation tolerance and integrating readout circuitry on the same substrate, compared with the hybrid pixel sensors and charge coupled devices. Thus, the CPS is a good candidate for tracking the charged particles in vertex detectors and beam telescopes.The power distribution becomes an important issue in the future detectors, since a considerable amount of sensors will be installed. Unfortunately, the independent powering has been proved to fail. In order to solve the power distribution challenges and to provide noiseless voltages, this thesis focuses on the design of a low noise, limited area, low power consumption and full on-chip power management in CPS chips. The CPS are firstly introduced drawing the design requirements of the power management. The power distribution dedicated to CPS chips is then proposed, in which the power management is utilized as the second power conversion stage. Two full on-chip regulators are proposed to generate the analog power supply voltage and the reference voltage required by correlated double sampling operation, respectively. Two prototypes have verified these regulators. They can meet the requirements of CPS. Moreover, the power management techniques and the radiation tolerance design are also presented in this thesis.STRASBOURG-Bib.electronique 063 (674829902) / SudocSudocFranceF

Etude et amélioration de capteurs monolithiques actifs à pixels résistants aux rayonnements pour reconstruire la trajectoire des particules chargées

Les capteurs monolithiques actifs à pixels (Monolithic Active Pixel Sensors, MAPS) sont de bons candidats pour être utilisés dans des expériences en Physique des Hautes Énergies (PHE) pour la détection des particules chargées. Dans les applications en PHE, des puces MAPS sont placées dans le voisinage immédiat du point d interaction et sont directement exposées au rayonnement intense de leur environnement. Dans cette thèse, nous avons étudié et amélioré la résistance aux radiations des MAPS. Les effets principaux de l irradiation et le progrès de la recherche sur les MAPS sont étudiés tout d'abord. Nous avons constaté que les cœurs des SRAM IP incorporées dans la puce MAPS limitent sensiblement la tolérance aux radiations de la puce MAPS entière. Aussi, pour améliorer la radiorésistance des MAPS, trois mémoires radiorésistantes sont conçues et évaluées pour les expériences en PHE. Pour remplacer les cœurs des IP SRAM, une SRAM radiorésistante est développée sur une petite surface. Pour les procédés de plus petit taille de grille des transistors, dans lequel les effets SEU (Single Event Upset) deviennent significatifs, une SRAM radiorésistante avec une tolérance SEU accrue est réalisée à l aide d un algorithme de détection et de correction d'erreurs (Error Detection And Correction, EDAC) et un stockage entrelacé des bits. Afin d'obtenir une tolérance aux rayonnements et une densité de micro-circuits plus élevées, une mémoire à double accès avec une cellule à 2 transistors originale est développée et évaluée pour des puces MAPS futures. Enfin, la radiorésistance des puces MAPS avec des nouveaux procédés disponibles est étudiée, et les travaux futurs sont proposés.Monolithic Active Pixel Sensors (MAPS) are good candidates to be used in High Energy Physics (HEP) experiments for charged particle detection. In the HEP applications, MAPS chips are placed very close to the interaction point and are directly exposed to harsh environmental radiation. This thesis focuses on the study and improvement of the MAPS radiation hardness. The main radiation effects and the research progress of MAPS are studied firstly. During the study, the SRAM IP cores built in MAPS are found limiting the radiation hardness of the whole MAPS chips. Consequently, in order to improve the radiation hardness of MAPS, three radiation hard memories are designed and evaluated for the HEP experiments. In order to replace the SRAM IP cores, a radiation hard SRAM is developed on a very limited area. For smaller feature size processes, in which the single event upset (SEU) effects get significant, a radiation hard SRAM with enhanced SEU tolerance is implemented by an error detection and correction algorithm and a bit-interleaving storage. In order to obtain higher radiation tolerance and higher circuitry density, a dual-port memory with an original 2-transistor cell is developed and evaluated for future MAPS chips. Finally, the radiation hardness of the MAPS chips using new available processes is studied, and the future works are prospected.STRASBOURG-Bib.electronique 063 (674829902) / SudocSudocFranceF

Multi-Access Edge Computing (MEC) Based on MIMO: A Survey

With the rapid development of wireless communication technology and the emergence of intelligent applications, higher requirements have been put forward for data communication and computing capacity. Multi-access edge computing (MEC) can handle highly demanding applications by users by sinking the services and computing capabilities of the cloud to the edge of the cell. Meanwhile, the multiple input multiple output (MIMO) technology based on large-scale antenna arrays can achieve an order-of-magnitude improvement in system capacity. The introduction of MIMO into MEC takes full advantage of the energy and spectral efficiency of MIMO technology, providing a new computing paradigm for time-sensitive applications. In parallel, it can accommodate more users and cope with the inevitable trend of continuous data traffic explosion. In this paper, the state-of-the-art research status in this field is investigated, summarized and analyzed. Specifically, we first summarize a multi-base station cooperative mMIMO-MEC model that can easily be expanded to adapt to different MIMO-MEC application scenarios. Subsequently, we comprehensively analyze the current works, compare them to each other and summarize them, mainly from four aspects: research scenarios, application scenarios, evaluation indicators and research issues, and research algorithms. Finally, some open research challenges are identified and discussed, and these indicate the direction for future research on MIMO-MEC

Precise Multiphase Clock Generation Using Low-Jitter Delay-Locked Loop Techniques for Positron Emission Tomography Imaging

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Enhanced Electromagnetic Coupling in the Walnut-Shaped Nanostructure Array

It is a challenging yet valuable work to prepare a surface-enhanced Raman scattering (SERS) substrate with low cost and high performance by simple methods. In this study, the Ag nanoparticles were sputtered on PS spheres by the magnetron sputtering, which was used as the mask to create the nanostructures by etching the spheres. Because of the heating effect in the etching process, the Ag nanoparticles gathered on the surfaces of PS spheres when the etching time was 60 s. Strong electromagnetic coupling was observed between the gathered Ag nanoparticles as confirmed by FDTD simulation and SERS signals from the probe molecule 4-mercaptobenzoic acid. This structure showed the detection limit for thiram down to 10−8 M

Using gait videos to automatically assess anxiety

Background: In recent years, the number of people with anxiety disorders has&nbsp;increased worldwide. Methods for identifying anxiety through objective clues are&nbsp;not yet mature, and the reliability and validity of existing modeling methods have&nbsp;not been tested. The objective of this paper is to propose an automatic anxiety&nbsp;assessment model with good reliability and validity. Methods: This study collected 2D gait videos and Generalized Anxiety Disorder&nbsp;(GAD-7) scale data from 150 participants. We extracted static and dynamic time-domain features and frequency-domain features from the gait videos and used&nbsp;various machine learning approaches to build anxiety assessment models. We&nbsp;evaluated the reliability and validity of the models by comparing the influence of&nbsp;factors such as the frequency-domain feature construction method, training data&nbsp;size, time-frequency features, gender, and odd and even frame data on themodel. Results: The results show that the number of wavelet decomposition layers has&nbsp;a significant impact on the frequency-domain feature modeling, while the size of&nbsp;the gait training data has little impact on the modeling e ect. In this study, the&nbsp;time-frequency features contributed to the modeling, with the dynamic features&nbsp;contributingmore than the static features.Ourmodel predicts anxiety significantly&nbsp;better in women than inmen (rMale = 0.666, rFemale = 0.763, p &lt; 0.001). The best&nbsp;correlation coe cient between the model prediction scores and scale scores for all participants is 0.725 (p &lt; 0.001). The correlation coe cient between themodel&nbsp;prediction scores for odd and even frame data is 0.801&sim;0.883 (p &lt; 0.001).&nbsp; Conclusion: This study shows that anxiety assessment based on 2D gait video modeling is reliable and e ective. Moreover, we provide a basis for the&nbsp;development of a real-time, convenient and non-invasive automatic anxiety&nbsp;assessment method.</p