Les travaux de thèse présentés dans ce manuscrit portent sur le développement d'une nouvelle architecture de transmission spécifiquement dédiée aux réseaux de capteurs sans fils et adaptée aux caractéristiques particulières de ceux-ci. L'approche, basée sur les techniques de radio impulsionnelle pour la transmission à large bande, est développée selon deux aspects de recherche principaux: fonctionnel et matériel. L'aspect fonctionnel vise à définir les caractéristiques du signal transmis ainsi que les algorithmes de traitement (modulation et démodulation) associés. Plus largement, il s'agit de définir l'architecture fonctionnelle de la chaîne de transmission, selon deux modes différents d'exploitation: mono-utilisateur et multi-utilisateurs. L'approche proposée pour transmettre des signaux impulsionnels, est basé sur l'emploi de la transformée discrète en paquets d'ondelettes (DWPT) au niveau du récepteur et de la transformée inverse au niveau de l'émetteur (IDWPT). La nature orthogonale des ondelettes permet de réaliser, sans nécessiter une couche MAC complexe, des communications multi-utilisateurs, simultanées ou non, sur un canal large bande, grâce à la forte discrimination entre les impulsions transmises. Le deuxième aspect porte sur le développement des architectures matérielles permettant l'implantation des algorithmes de traitement développés dans la partie fonctionnelle. La recherche de performances élevées (ratio élevé entre vitesse de traitement et coût matériel) et flexibilité (configurabilité, extensibilité), est particulièrement important dans les fonctionnalités liées aux transformées discrètes en paquets d'ondelettes qui constituent le cœur critique de la chaîne de transmission. Des techniques de parallélisation massive et générique sont développées et mises en œuvre, permettant d'atteindre les niveaux de performances et de flexibilité requis. La validation a été réalisée à l'aide respectivement de modélisations et imulations sous Simulink/Matlab (de MathWorks) pour les aspects fonctionnels et de modélisations VHDL (au niveau RTL [Register Transfer Level]) et d'implantations sur FPGA pour les aspects matériels / The thesis work presented in this manuscript focuses on the development of a new transmission architecture specifically dedicated to wireless sensor networks and adapted to the particular characteristics of the later. The approach, based on impulse radio techniques for wideband transmission, is developed according to two main research aspects: functional and hardware. The functional aspect aims at defining the characteristics of the transmitted signal as well as the associated processing algorithms (modulation and demodulation). More broadly, it comes to define the functional architecture of the transmission chain, according to two different operating modes: mono- and multi-user. The proposed approach for transmitting pulse signals is based on the use of the discrete wavelet packet transform (DWPT) at the receiver and the inverse transform (IDWPT) at the transmitter. The orthogonal nature of the wavelets makes it possible, without needing a complex MAC layer, to make multi-user communications, either simultaneous or not, over a wideband channel, thanks to the strong discrimination between the transmitted pulses. The second aspect relates to the development of hardware architectures allowing the implementation of the processing algorithms developed in the functional part. The search for high performance (high ratio between processing speed and hardware cost) and flexibility (configurability, extensibility) is particularly important in the functionality related to the discrete wavelet packet transform which constitutes the critical core of the transmission chain. Massive and generic parallelization techniques are developed and implemented to achieve the required levels of performance and flexibility. Validation was carried out using respectively Simulink/Matlab (MathWorks) modeling and simulation for the functional aspects, and VHDL modeling (at the Register Transfer Level -- RTL) and FPGA implementations for the hardware aspects

<p>  </p> <p>Present barriers to electric vehicle (EV) adoption include cost and range anxiety. Dynamic wireless power transfer (DWPT) systems, which send energy from an in-road transmitter to a vehicle in motion, offer potential remedies to both issues. Specifically, they reduce the size and charging needs of the relatively expensive battery system by supplying the power required for vehicle motion and operation. Recently, Purdue researchers have been exploring the development of inductive DWPT systems for Class 8 and 9 trucks operating at highway speeds. This research has included the design of transmitter/receiver coils as well as compensation circuits and power electronics that are required to efficiently transmit 200 kW-level power across a large air gap.</p> <p>In this thesis, a focus is on the derivation of electromagnetic and thermal models that are used to support the design and validation of DWPT systems. Specifically, electromagnetic models have been derived to predict the volume and loss of ferrite-based AC inductors and film capacitor used in compensation circuits. A thermal equivalent circuit of the transmitter has been derived to predict the expected coil and pavement temperatures in DWPT systems that utilize either single- or three-phase transmitter topologies. A description of these models, along with their validation using finite element-based simulation and their use in multi-objective optimization of DWPT systems is provided.</p>

<p dir="ltr">This thesis investigates the embedment of Dynamic Wireless Power Transfer (DWPT) components within two pavement test sections, aiming to evaluate their mechanical and thermal responses. The integration of DWPT components into the pavement structure, while enabling dynamic power delivery to EVs, alters the conventional geometric design of a typical pavement, potentially influencing their short-term and long-term durability and integrity. Hence, to ensure the integrity and efficiency of both the embedded system and the surrounding structure, it is essential to understand how integrating these components influence the pavement's performance.</p><p dir="ltr">Conducted at the Accelerated Pavement Testing (APT) facility of the Indiana Department of Transportation (INDOT), the study evaluates over the course of 25,000 APT traffic passes, the mechanical and thermal responses of both, a flexible and rigid pavement test section. Each test section features a Charging Unit (CU), a concrete slab upon which the DWPT components are placed. The construction of the flexible pavement involved milling down 2 in. of the existing pavement surface, while the rigid pavement required complete demolition of the existing pavement. The flexible pavement’s CU is composed of Class A concrete and the rigid pavement's CU features magnetizable concrete, a type of concrete composed of ferrite particles embedded in a cement matrix. Among the two pavement sections, only the rigid pavement exhibited visible distress, identified as a mid-panel crack. Several factors contributed to the crack formation, including inadequate adhesion between concrete interfaces, concrete mix segregation, material variations, construction issues, and nonuniform load distribution. The manual construction procedures, which were employed to prevent disrupting the embedded DWPT components and sensor instrumentation, and the one-week gap between casting the CU and the surrounding slab might have further influenced the adhesion strength of the rigid pavement section.</p><p dir="ltr">By examining the construction techniques employed, challenges encountered, and resulting behavior of both pavement test sections, this study provides insights into the construction and performance implications of DWPT component integration into pavements, as evidenced by the responses observed in the test sections. This thesis thereby contributes to the ongoing research efforts on investigating the impact such integration has on the surrounding structure's integrity.</p>

This Thesis deals with a method to enforce the intellectual property rights and protect digital media from tampering – Digital Audio Watermarking. The main aim of this work is implement an audio watermarking algorithm. The theoretical part defined basic terms, methods and processes, which are used in this area. The practical part shows a process of embedding the digital signature into a host signal and her backward extraction. The embedding rule used spread spectrum technique and a psychoacoustic model. The implemented psychoacoustic model involves two properties of the human auditory system which are frequency masking and representation the frequency scale on limited bands called critical bands. The model is relatively new and based on the DWPT. In terms of above model is then the digital watermark embedded in the wavelet domain. This algorithm is implemented in technical software MATLAB. One part of this work focuses on robustness tests of the algorithm. Common signal processing modifications are applied to the watermarked audio as follows: Cutting of the audio, re-sampling, lossy compression, filtering, equalization, modulation effects, noise addition. The last part of the thesis presents subjective and objective methods usable in order to judge the influence of watermarking embedding on the quality of audio tracks called transparency.