20 research outputs found

    Preserving data integrity of encoded medical images: the LAR compression framework

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    International audienceThrough the development of medical imaging systems and their integration into a complete information system, the need for advanced joint coding and network services becomes predominant. PACS (Picture Archiving and Communication System) aims to acquire, store and compress, retrieve, present and distribute medical images. These systems have to be accessible via the Internet or wireless channels. Thus protection processes against transmission errors have to be added to get a powerful joint source-channel coding tool. Moreover, these sensitive data require confidentiality and privacy for both archiving and transmission purposes, leading to use cryptography and data embedding solutions. This chapter introduces data integrity protection and developed dedicated tools of content protection and secure bitstream transmission for medical encoded image purposes. In particular, the LAR image coding method is defined together with advanced securization services

    Schémas de tatouage d'images, schémas de tatouage conjoint à la compression, et schémas de dissimulation de données

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    In this manuscript we address data-hiding in images and videos. Specifically we address robust watermarking for images, robust watermarking jointly with compression, and finally non robust data-hiding.The first part of the manuscript deals with high-rate robust watermarking. After having briefly recalled the concept of informed watermarking, we study the two major watermarking families : trellis-based watermarking and quantized-based watermarking. We propose, firstly to reduce the computational complexity of the trellis-based watermarking, with a rotation based embedding, and secondly to introduce a trellis-based quantization in a watermarking system based on quantization.The second part of the manuscript addresses the problem of watermarking jointly with a JPEG2000 compression step or an H.264 compression step. The quantization step and the watermarking step are achieved simultaneously, so that these two steps do not fight against each other. Watermarking in JPEG2000 is achieved by using the trellis quantization from the part 2 of the standard. Watermarking in H.264 is performed on the fly, after the quantization stage, choosing the best prediction through the process of rate-distortion optimization. We also propose to integrate a Tardos code to build an application for traitors tracing.The last part of the manuscript describes the different mechanisms of color hiding in a grayscale image. We propose two approaches based on hiding a color palette in its index image. The first approach relies on the optimization of an energetic function to get a decomposition of the color image allowing an easy embedding. The second approach consists in quickly obtaining a color palette of larger size and then in embedding it in a reversible way.Dans ce manuscrit nous abordons l’insertion de données dans les images et les vidéos. Plus particulièrement nous traitons du tatouage robuste dans les images, du tatouage robuste conjointement à la compression et enfin de l’insertion de données (non robuste).La première partie du manuscrit traite du tatouage robuste à haute capacité. Après avoir brièvement rappelé le concept de tatouage informé, nous étudions les deux principales familles de tatouage : le tatouage basé treillis et le tatouage basé quantification. Nous proposons d’une part de réduire la complexité calculatoire du tatouage basé treillis par une approche d’insertion par rotation, ainsi que d’autre part d’introduire une approche par quantification basée treillis au seind’un système de tatouage basé quantification.La deuxième partie du manuscrit aborde la problématique de tatouage conjointement à la phase de compression par JPEG2000 ou par H.264. L’idée consiste à faire en même temps l’étape de quantification et l’étape de tatouage, de sorte que ces deux étapes ne « luttent pas » l’une contre l’autre. Le tatouage au sein de JPEG2000 est effectué en détournant l’utilisation de la quantification basée treillis de la partie 2 du standard. Le tatouage au sein de H.264 est effectué à la volée, après la phase de quantification, en choisissant la meilleure prédiction via le processus d’optimisation débit-distorsion. Nous proposons également d’intégrer un code de Tardos pour construire une application de traçage de traîtres.La dernière partie du manuscrit décrit les différents mécanismes de dissimulation d’une information couleur au sein d’une image en niveaux de gris. Nous proposons deux approches reposant sur la dissimulation d’une palette couleur dans son image d’index. La première approche consiste à modéliser le problème puis à l’optimiser afin d’avoir une bonne décomposition de l’image couleur ainsi qu’une insertion aisée. La seconde approche consiste à obtenir, de manière rapide et sûre, une palette de plus grande dimension puis à l’insérer de manière réversible

    Multimedia

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    The nowadays ubiquitous and effortless digital data capture and processing capabilities offered by the majority of devices, lead to an unprecedented penetration of multimedia content in our everyday life. To make the most of this phenomenon, the rapidly increasing volume and usage of digitised content requires constant re-evaluation and adaptation of multimedia methodologies, in order to meet the relentless change of requirements from both the user and system perspectives. Advances in Multimedia provides readers with an overview of the ever-growing field of multimedia by bringing together various research studies and surveys from different subfields that point out such important aspects. Some of the main topics that this book deals with include: multimedia management in peer-to-peer structures & wireless networks, security characteristics in multimedia, semantic gap bridging for multimedia content and novel multimedia applications

    Assessment and Real Time Implementation of Wireless Communications Systems and Applications in Transportation Systems

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    Programa Oficial de Doutoramento en Tecnoloxías da Información e das Comunicacións en Redes Móbiles. 5029V01[Resumo] Os sistemas de comunicación sen fíos de cuarta e quinta xeración (4G e 5G) utilizan unha capa física (PHY) baseada en modulacións multiportadora para a transmisión de datos cun gran ancho de banda. Este tipo de modulacións proporcionan unha alta eficiencia espectral á vez que permiten corrixir de forma sinxela os efectos da canle radio. Estes sistemas utilizan OFDMA como mecanismo para a repartición dos recursos radio dispoñibles entre os diferentes usuarios. Este repartimento realízase asignando un subconxunto de subportadoras a cada usuario nun instante de tempo determinado. Isto aporta unha gran flexibilidade ó sistema que lle permite adaptarse tanto ós requisitos de calidade de servizo dos usuarios como ó estado da canle radio. A capa de acceso ó medio (MAC) destes sistemas encárgase de configurar os diversos parámetros proporcionados pola capa física OFDMA, ademais de xestionar os diversos fluxos de información de cada usuario, transformando os paquetes de capas superiores en paquetes da capa física. Neste traballo estúdase o deseño e implementación das capas MAC e PHY de sistemas de comunicación 4G ademais da súa aplicabilidade en sistemas de transporte ferroviarios. Por unha parte, abórdase o deseño e implementación en tempo real do estándar WiMAX. Estúdanse os mecanismos necesarios para establecer comunicacións bidireccionais entre unha estación base e múltiples dispositivos móbiles. Ademais, estúdase como realizar esta implementación nunha arquitectura hardware baseada en DSPs e FPGAs, na que se implementan as capas MAC e PHY. Dado que esta arquitectura ten uns recursos computacionais limitados, tamén se estudan as necesidades de cada módulo do sistema para poder garantir o funcionamento en tempo real do sistema completo. Por outra parte, tamén se estuda a aplicabilidade dos sistemas 4G a sistemas de transporte públicos. Os sistemas de comunicacións e sinalización son unha parte vital para os sistemas de transporte ferroviario e metro. As comunicacións sen fíos utilizadas por estes sistemas deben ser robustas e proporcionar unha alta fiabilidade para permitir a supervisión, control e seguridade do tráfico ferroviario. Para levar a cabo esta avaliación de viabilidade realízanse simulacións de redes de comunicacións LTE en contornos de transporte ferroviarios, comprobando o cumprimento dos requisitos de fiabilidade e seguridade. Realízanse diferentes simulacións do sistema de comunicacións para poder ser avaliadas e seleccionar a configuración e arquitectura do sistema máis axeitada en función do escenario considerado. Tamén se efectúan simulacións de redes baseadas en Wi-Fi, dado que é a solución máis utilizada nos metros, para confrontar os resultados cos obtidos para LTE. Para que os resultados das simulacións sexan realistas débense empregar modelos de propagación radio axeitados. Nas simulacións utilízanse tanto modelos deterministas como modelos baseados nos resultados de campañas de medida realizadas nestes escenarios. Nas simulacións empréganse os diferentes fluxos de información destes escenarios para comprobar que se cumpren os requisitos de calidade de servicio (QoS). Por exemplo, os fluxos críticos para o control ferroviario, como European Train Control System (ETCS) ou Communication-Based Train Control (CBTC), necesitan unha alta fiabilidade e un retardo mínimo nas comunicacións para garantir o correcto funcionamento do sistema.[Resumen] Los sistemas de comunicación inalámbricos de cuarta y quinta generación (4G y 5G) utilizan una capa física (PHY) basada en modulaciones multiportadora para la transmisión de datos con un gran ancho de banda. Este tipo de modulaciones han demostrado tener una alta eficiencia espectral a la vez que permiten corregir de forma sencilla los efectos del canal radio. Estos sistemas utilizan OFDMA como mecanismo para el reparto de los recursos radio disponibles entre los diferentes usuarios. Este reparto se realiza asignando un subconjunto de subportadoras a cada usuario en un instante de tiempo determinado. Esto aporta una gran flexibilidad al sistema que le permite adaptarse tanto a los requisitos de calidad de servicio de los usuarios como al estado del canal radio. La capa de acceso al medio (MAC) de estos sistemas se encarga de configurar los diversos parámetros proporcionados por la capa física OFDMA, además de gestionar los diversos flujos de información de cada usuario, transformando los paquetes de capas superiores en paquetes de la capa física. En este trabajo se estudia el diseño e implementación de las capas MAC y PHY de sistemas de comunicación 4G además de su aplicabilidad en sistemas de transporte ferroviarios. Por una parte, se aborda el diseño e implementación en tiempo real del estándar WiMAX. Se estudian los mecanismos necesarios para establecer comunicaciones bidireccionales entre una estación base y múltiples dispositivos móviles. Además, se estudia cómo realizar esta implementación en una arquitectura hardware basada en DSPs y FPGAs, en la que se implementan las capas MAC y PHY. Dado que esta arquitectura tiene unos recursos computacionales limitados, también se estudian las necesidades de cada módulo del sistema para poder garantizar el funcionamiento en tiempo real del sistema completo. Por otra parte, también se estudia la aplicabilidad de los sistemas 4G a sistemas de transporte públicos. Los sistemas de comunicaciones y señalización son una parte vital para los sistemas de transporte ferroviario y metro. Las comunicaciones inalámbricas utilizadas por estos sistemas deben ser robustas y proporcionar una alta fiabilidad para permitir la supervisión, control y seguridad del tráfico ferroviario. Para llevar a cabo esta evaluación de viabilidad se realizan simulaciones de redes de comunicaciones LTE en entornos de transporte ferroviarios, comprobando si se cumplen los requisitos de fiabilidad y seguridad. Se realizan diferentes simulaciones del sistema de comunicaciones para poder ser evaluados y seleccionar la configuración y arquitectura del sistema más adecuada en función del escenario planteado. También se efectúan simulaciones de redes basadas en Wi-Fi, dado que es la solución más utilizada en los metros, para comparar los resultados con los obtenidos para LTE. Para que los resultados de las simulaciones sean realistas se deben utilizar modelos de propagación radio apropiados. En las simulaciones se utilizan tanto modelos deterministas como modelos basados en los resultados de campañas de medida realizadas en estos escenarios. En las simulaciones se utilizan los diferentes flujos de información de estos escenarios para comprobar que se cumplen sus requisitos de calidad de servicio. Por ejemplo, los flujos críticos para el control ferroviario, como European Train Control System (ETCS) o Communication-Based Train Control (CBTC), necesitan una alta fiabilidad y un retardo bajo en las comunicaciones para garantizar el correcto funcionamiento del sistema.[Abstract] The fourth and fifth generation wireless communication systems (4G and 5G) use a physical layer (PHY) based on multicarrier modulations for data transmission using high bandwidth. This type of modulations has shown to provide high spectral efficiency while allowing low complexity radio channel equalization. These systems use OFDMA as a mechanism for distributing the available radio resources among different users. This allocation is done by assigning a subset of subcarriers to each user in a given instant of time. This provides great flexibility to the system that allows it to adapt to both the quality of service requirements of users and the radio channel state. The media access layer (MAC) of these systems is in charge of configuring the multiple OFDMA PHY layer parameters, in addition to managing the data flows of each user, transforming the higher layer packets into PHY layer packets. This work studies the design and implementation of MAC and PHY layers of 4G communication systems as well as their applicability in rail transport systems. On the one hand, the design and implementation in real time of the WiMAX standard is addressed. The required mechanisms to establish bidirectional communications between a base station and several mobile devices are also evaluated. Moreover, a MAC layer and PHY layer implementation is presented, using a hardware architecture based in DSPs and FPGAs. Since this architecture has limited computational resources, the requirements of each processing block of the system are also studied in order to guarantee the real time operation of the complete system. On the other hand, the applicability of 4G systems to public transportation systems is also studied. Communications and signaling systems are a vital part of rail and metro transport systems. The wireless communications used by these systems must be robust and provide high reliability to enable the supervision, control and safety of rail traffic. To carry out this feasibility assessment, LTE communications network simulations are performed in rail transport environments to verify that reliability and safety requirements are met. Several simulations are carried out in order to evaluate the system performance and select the most appropriate system configuration in each case. Simulations of Wi-Fi based networks are also carried out, since it is the most used solution in subways, to compare the results with those obtained for LTE. To perform the simulations correctly, appropriate radio propagation models must be used. Both deterministic models and models based on the results of measurement campaigns in these scenarios are used in the simulations. The simulations use the different information flows present in the railway transportation systems to verify that its quality of service requirements are met. For example, critical flows for railway control, such as the European Train Control System (ETCS) or Communication-Based Train Control (CBTC), require high reliability and low delay communications to ensure the proper functioning of the system

    Signal processing techniques for mobile multimedia systems

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    Recent trends in wireless communication systems show a significant demand for the delivery of multimedia services and applications over mobile networks - mobile multimedia - like video telephony, multimedia messaging, mobile gaming, interactive and streaming video, etc. However, despite the ongoing development of key communication technologies that support these applications, the communication resources and bandwidth available to wireless/mobile radio systems are often severely limited. It is well known, that these bottlenecks are inherently due to the processing capabilities of mobile transmission systems, and the time-varying nature of wireless channel conditions and propagation environments. Therefore, new ways of processing and transmitting multimedia data over mobile radio channels have become essential which is the principal focus of this thesis. In this work, the performance and suitability of various signal processing techniques and transmission strategies in the application of multimedia data over wireless/mobile radio links are investigated. The proposed transmission systems for multimedia communication employ different data encoding schemes which include source coding in the wavelet domain, transmit diversity coding (space-time coding), and adaptive antenna beamforming (eigenbeamforming). By integrating these techniques into a robust communication system, the quality (SNR, etc) of multimedia signals received on mobile devices is maximised while mitigating the fast fading and multi-path effects of mobile channels. To support the transmission of high data-rate multimedia applications, a well known multi-carrier transmission technology known as Orthogonal Frequency Division Multiplexing (OFDM) has been implemented. As shown in this study, this results in significant performance gains when combined with other signal-processing techniques such as spa ce-time block coding (STBC). To optimise signal transmission, a novel unequal adaptive modulation scheme for the communication of multimedia data over MIMO-OFDM systems has been proposed. In this system, discrete wavelet transform/subband coding is used to compress data into their respective low-frequency and high-frequency components. Unlike traditional methods, however, data representing the low-frequency data are processed and modulated separately as they are more sensitive to the distortion effects of mobile radio channels. To make use of a desirable subchannel state, such that the quality (SNR) of the multimedia data recovered at the receiver is optimized, we employ a lookup matrix-adaptive bit and power allocation (LM-ABPA) algorithm. Apart from improving the spectral efficiency of OFDM, the modified LM-ABPA scheme, sorts and allocates subcarriers with the highest SNR to low-frequency data and the remaining to the least important data. To maintain a target system SNR, the LM-ABPA loading scheme assigns appropriate signal constella tion sizes and transmit power levels (modulation type) across all subcarriers and is adapted to the varying channel conditions such that the average system error-rate (SER/BER) is minimised. When configured for a constant data-rate load, simulation results show significant performance gains over non-adaptive systems. In addition to the above studies, the simulation framework developed in this work is applied to investigate the performance of other signal processing techniques for multimedia communication such as blind channel equalization, and to examine the effectiveness of a secure communication system based on a logistic chaotic generator (LCG) for chaos shift-keying (CSK)

    Implementação de Tx/Rx banda base para 802.11-2007 em FPGA

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    Mestrado em Engenharia Electrónica e TelecomunicaçõesO trabalho apresentado nesta dissertação teve como objectivo o desenvolvimento da camada física de um sistema de transmissão e recepção de sinais OFDM baseados no standard IEEE 802.11-2007. O sistema desenvolvido inclui geração de dados aleatórios, modulador QAM, inserção de pilotos e subportadora DC, IFFT com adição de Prefixo Cíclico, buffer de saída e o consequente oposto para o receptor. A dissertação encontra-se dividida em duas partes principais. Na primeira parte, o sistema foi projectado e simulado em Matlab através do ambiente Simulink com o auxílio dos blocos da Xilinx inseridos no seu software System Generator for DSP. Na segunda parte, foram adicionadas DACʼs ao transmissor e o próprio foi compilado para um bloco e testado no XtremeDSP Development Kit-IV da Nallatech que inclui uma Field-Programmable Gate Array. Todos os módulos foram desenhados usando os blocos do System Generator for DSP da Xilinx. O kit está conectado ao computador através de uma interface PCI. Os dados obtidos são exibidos em Matlab para a primeira parte e num osciloscópio para a segunda parte.It was the objective of this dissertation the development of the Physical Layer of an IEEE 802.11-2007 Transmitter-Receiver system for generating OFDM signals. The developed design includes random Data Generation, QAM Modulator, Pilots and DC subcarrier insertion, IFFT with Cyclic Prefix insertion, an Output Buffer and the subsequent opposite for its receiver. This dissertation was divided in two main segments. In the first segment, the system was designed and simulated in Matlab through the Simulink environment using Xilinxʼs System Generator for DSP blocks. In the second part, DACʼs where added to the transmitter in order to compile it into a single block and test it on Nallatechʼs XtremeDSP Development Kit-IV, which includes a Field-Programmable Gate Array. All modules were designed using Xilinxʼs System Generator for DSP blocks. The kit is connected to the computer through a PCI interface. Output data is displayed on the Matlab environment for part one and on an oscilloscope for part two

    Low Earth orbit microsatellite constellation utilizing satellite Hellas Sat 5 as a relay

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    Με δεδομένο ότι βρισκόμαστε σε μια εποχή ορόσημο για την ανάπτυξη στον διαστημικό τομέα, το σύνολο σχεδόν όλων των ανεπτυγμένων χωρών έχει συνειδητοποιήσει ότι η επένδυση στο σύνολο των διαστημικών τεχνολογιών αποτελεί μονόδρομο ανάπτυξης και ευημερίας. Τα δαπανούμενα ποσά είναι απολύτως ενδεικτικά της φρενίτιδας που επικρατεί στη λεγόμενη κούρσα του διαστήματος. Η εισαγωγή πλέον και του ιδιωτικού τομέα στη κούρσα αυτή έχει επιτρέψει την προώθηση του ανταγωνισμού κάτι το οποίο με τη σειρά του έχει ελαττώσει εντυπωσιακά το κόστος χρήσης και αξιοποίησης του διαστημικού τομέα. Αυτό το νέο διαστημικό οικοσύστημα που έχει αναπτυχθεί παγκοσμίως τις τελευταίες δεκαετίες, έχει επιτρέψει τη πρόσβαση στις διαστημικές τεχνολογίες από το σύνολο σχεδόν των χωρών του πλανήτη, τη στιγμή που κατά τις προηγούμενες δεκαετίες, οι μοναδικές χώρες που είχαν τη δυνατότητα να επενδύσουν στον τομέα ήταν οι ΗΠΑ και οι Ρωσία. Δορυφορική παρατήρηση της γης, πλοήγηση, αποτροπή φυσικών καταστροφών, εξερεύνηση του διαστήματος, επιστημονική ανάλυση της επιφάνειας του εδάφους, εκμετάλλευση φυσικών πόρων αλλά και πολιτικές και στρατιωτικές τηλεπικοινωνίες, είναι μόνο μερικές από τις νέες τεχνολογίες που έχει να προσφέρει ο διαστημικός τομέας. Κάθε ένας από αυτούς τους τομείς μπορεί δυνητικά να αποτελέσει πυλώνα ανάπτυξης αν αξιοποιηθεί σωστά και πλέον όλες οι χώρες έχουν συνειδητοποιήσει πως η επένδυση σε κάποιον ή και σε όλους αυτούς τους τομείς μπορούν να επιφέρουν πολλαπλά οφέλη. Ένα χαρακτηριστικό παράδειγμα του νέου διαστημικού οικοσυστήματος που έχει διαμορφωθεί κατά τις τελευταίες δεκαετίες και που δείχνει το πόσο πολύ επενδύουν πλέον οι χώρες στον διαστημικό τομέα, είναι ο υπερδιπλασιαμός των ενεργών δορυφορικών συστημάτων κατά τη πενταετία 2015 – 2020, ιδιαίτερα των τηλεπικοινωνιακών. Αξίζει να σημειωθεί πως τον Δεκέμβριο του 2015, σύμφωνα με τα στοιχεία της UCS, ο αριθμός των ενεργών δορυφόρων του έτους ανήλθε σε 1.381, αριθμός ο οποίος κατά τον ίδιο μήνα του έτους 2020 είχε φτάσει τους 3.372. Έχοντας πει όλα τα παραπάνω, η παρούσα διπλωματική εργασία στοχεύει στην παρουσίαση μιας ολοκληρωμένης ανάλυσης όλων των απαιτούμενων βημάτων που πρέπει να εξετάσει ένας μηχανικός / σχεδιαστής συστημάτων προκειμένου να κατασκευάσει και να αναπτύξει μια πλήρως λειτουργική και αξιόπιστη δορυφορική ζεύξη επικοινωνίας. Η μεθοδολογία περιλαμβάνει μια πλήρη περιγραφή των βασικών νόμων του διαστημικού περιβάλλοντος καθώς και μια εκτενή ανάλυση της τροχιακής μηχανικής και των παραμέτρων. Η ιδέα ήταν να παρουσιαστεί πώς η θεωρία μπορεί να εφαρμοστεί σε μια πραγματική δορυφορική προσομοίωση καθώς και πώς επηρεάζεται από αυτήν. Το τελευταίο βήμα ήταν ο σχεδιασμός και η κατασκευή ενός πραγματικού συστήματος δορυφορικής επικοινωνίας σε ένα εξειδικευμένο λογισμικό και η παρουσίαση των αποτελεσμάτων. Το κύριο συμπέρασμα της παραπάνω υλοποίησης είναι το γεγονός ότι μέσω της χρήσης ενός αστερισμού δορυφόρων χαμηλής Γήινης τροχιάς σε συνδυασμό με έναν γεωστατικό δορυφόρο που χρησιμοποιείται αναμεταδότης, είναι δυνατό να επιτευχθεί μια ανθεκτική και αξιόπιστη επικοινωνιακή ζεύξη με εξαιρετικά υψηλούς ρυθμούς μετάδοσης δεδομένων και σχεδόν παγκόσμια κάλυψη.Given that we are in a landmark era of the space sector development , most countries have realized that an investment in space technologies is the only way for development and prosperity. The invested budgets are absolutely indicative of the so-called space race. The introduction of the private sector in this race has allowed the promotion of competition, which in turn has dramatically reduced the cost of using and exploiting the space sector. This new space ecosystem that has been developed worldwide in recent decades, has allowed access to space technologies from almost all countries on the planet, while in previous decades, the only countries that had the opportunity to invest in the sector were USA and Russia. Satellite earth observation, navigation, prevention of natural disasters, space exploration, scientific analysis of the earth's surface, exploitation of natural resources, but also civil and military telecommunications, are just some of the new technologies that the space sector has to offer. Each of these sectors can potentially be a pillar of development if exploited properly and almost all of the modern countries have realized that investing in one or all of these sectors can offer multiple benefits. A typical example of the new space ecosystem that has been formed during the last decades and that shows how much money countries are now investing in the space sector, is the dramatic increase of the active satellite systems during the years 2015 – 2020, especially the telecommunication ones. It is worth mentioning that in December 2015, according to UCS data, the number of active satellites was 1.381, a number which during the same month in 2020 reached the astonishing number of 3.372. The rapid development of the space sector combined with the cost reducing methods that private sectors have introduced, is showing that the imminent future seems to be very promising. Having said all of the above, this thesis aims at presenting a comprehensive analysis of all the required steps that a system engineer / designer must consider in order to build and deploy a fully functional and reliable satellite communication link. The methodology entails a fully description of the basic laws of the space environment as well as an extensive analysis of the orbital mechanics and parameters. The idea was to demonstrate how the theory can be utilized in an actual satellite project simulation as well as how it is affected by it. The last step was to design and build an actual satellite communication system on a specialized software and present the results. The main conclusion of the above implementation is the fact that through the use of a low Earth orbit satellite constellation combined with a geostationary satellite used as a relay, it’s possible to achieve a resilient and reliable communication link with exceptional high data rates and an almost worldwide coverage

    Dependable Embedded Systems

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    This Open Access book introduces readers to many new techniques for enhancing and optimizing reliability in embedded systems, which have emerged particularly within the last five years. This book introduces the most prominent reliability concerns from today’s points of view and roughly recapitulates the progress in the community so far. Unlike other books that focus on a single abstraction level such circuit level or system level alone, the focus of this book is to deal with the different reliability challenges across different levels starting from the physical level all the way to the system level (cross-layer approaches). The book aims at demonstrating how new hardware/software co-design solution can be proposed to ef-fectively mitigate reliability degradation such as transistor aging, processor variation, temperature effects, soft errors, etc. Provides readers with latest insights into novel, cross-layer methods and models with respect to dependability of embedded systems; Describes cross-layer approaches that can leverage reliability through techniques that are pro-actively designed with respect to techniques at other layers; Explains run-time adaptation and concepts/means of self-organization, in order to achieve error resiliency in complex, future many core systems
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