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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Tecnologias system on chip e CAN em sistemas de controle distribuído / System on chip and CAN technologies into distributed control systems

Jean Mimar Santa Cruz Yabarrena 23 May 2006 (has links)
Sistemas de controle precisam trabalhar com restrições temporais rigorosas para garantir seu correto funcionamento, sendo por isso considerados sistemas de tempo-real. Quando tais sistemas são distribuídos, as redes de sensores, atuadores e controladores estão interligados em geral, por redes de campo. Nesse contexto, as redes de campo desempenham um papel extremamente importante no comportamento global do sistema. O presente trabalho de pesquisa apresenta a descrição do processo de desenvolvimento de um system on-chip (SoC) para um sistema de controle. Diferentemente das abordagens clássicas, o trabalho está focado em implementar o sistema baseado em um paradigma diferenciado, baseado em lógica reprogramável. Apresenta-se o projeto e construção dos IP cores necessários para controlar um motor DC, utilizando o barramento control area network (CAN) para obter uma plataforma distribuída. A arquitetura on chip utilizada está baseada na especificação CoreConnect da IBM. São expostos, ainda, trabalhos de simulação tanto dos componentes isolados, como do sistema integrado, de forma a realizar uma comparação qualitativa do processo de desenvolvimento / Control systems require strict time constraints to work properly, being therefore considered real-time systems. When such systems are distributed, controllers, sensors, and actuators are generally interconnected by fieldbuses. In this context the fieldbuses play an important role in the system global behavior. This research presents the description of the development process of a system-on-chip SoC. Differentiated from the classical approaches, this work focus the implementation of a reprogrammable logic based system. This work explain the necessary IP cores implementation, allowing a DC motor control, using a control area network (CAN) bus to reach a distributed platform. The on-chip architecture used is based on the IBM CoreConnect specification. Moreover it shows isolated components and integral system simulations, in such a way to obtain a qualitative comparison of development processes
92

Uma rede Ethernet on chip parametrizável para aplicações DSP em FPGA / An Ethernet network on configurable DSP chip for applications in FPGA

Hélio Fernandes da Cunha Junior 03 June 2015 (has links)
Com o crescimento acelerado da complexidade das aplicações e softwares que exigem alto desempenho, o hardware e sua arquitetura passou por algumas mudanças para que pudesse atender essa necessidade. Uma das abordagens propostas e desenvolvidas para suportar essas aplicações, foi a integração de mais de um core de processamento em um único circuito integrado. Inicialmente, a comunicação utilizando barramento foi escolhida, pela sua vantagem de reuso comparado a ponto a ponto. No entanto, com o aumento acelerado da quantidade de cores nos Systems-on-Chip (SoC), essa abordagem passou a apresentar problemas para suportar a comunicação interna. Uma alternativa que vem sendo explorada é a Network-on-Chip (NoC), uma abordagem que propõe utilizar o conhecimento de redes comuns em projetos de comunicação interna de SoC. Esse trabalho fornece uma arquitetura de NoC completa, configurável, parametrizável e no padrão Ethernet. Os três módulos básicos da NoC, Network Adapter (NA), Link e Switch, são implementados e disponibilizados. Os resultados foram obtidos utilizando o FPGA Stratix IV da Altera. As métricas de desempenho utilizadas para validação da NoC são a área no FPGA e o atraso na comunicação. Os parâmetros disponibilizados são referentes as configurações dos módulos desenvolvidos, considerando características apresentadas de aplicações DSP (Digital Signal Processing). O experimento utilizando dois NAs, dois cores e um Switch precisou de 7310 ALUTs do FPGA EP4SGX230KF40C2ES o que corresponde a 4% dos seus recursos lógicos. O tempo gasto para a transmissão de um quadro ethernet de 64 Bytes foi de 422 ciclos de clock a uma frequência de 50MHz. / With the accelerated growth of the complexity of the software and applications that require high performance, hardware and its architecture has undergone a few changes so it could meet that need. One of the proposals and approaches developed to support these applications, was the integration of more than one core processing in a single integrated circuit. Initially, the bus communication architecture was chosen, using for its reuse benefit compared to point-to-point. However, with the cores number increase in Systems-on-Chip (SoC), this approach began to present problems to support internal communication. An alternative that has been explored is the Network-on-Chip (NoC), an approach that proposes to use knowledge of common networks on internal communication projects of SOC. This dissertation focuses is to provide a complete NoC architecture, configurable, customizable and on standard Ethernet. The three NoC basic modules, Network Adapter (NA), Link and Switch, are implemented. The results were obtained using the Stratix IV FPGA. The performance metrics used for NoC validation are silicon area and latency. The available parameters are related to developed modules settings, considering features presented of DSP applications. The experiment using two NA, two cores and one Switch needed 7310 FPGA ALUTs which corresponds to 4% of their logical resources. The time for the transmission of an ethernet frame of 64 Bytes was 422 clock cycles at 50 MHz.
93

Směrování ve vysokorychlostních počítačových sítích / Routing in High-speed Computer Networks

Vlček, Lukáš January 2013 (has links)
Goal of this master thesis is to introduce and bring up basics and principles of NetCOPE framework in many details using "first approach" method for exploration of its internal structures - mainly focusing on application core using VHDL for focus itself. Furthermore, this knowledge is used for design and implementation of filtration system for network traffic with more details within phase of design in VHDL language.
94

Optimisation des performances et de la complexité dans les architectures multiprocesseurs hétérogènes sur puce / Performance and complexity optimization in heterogeneous multiprocessors system on chip

Dammak Masmoudi, Bouthaina 06 November 2015 (has links)
Les travaux présentés dans cette thèse visent le développement d'une méthodologie capable d’estimer rapidement les performances d’une architecture MPSoC avec des instructions spécialisées. Pour ces architectures, l’outil proposé intègre une méthodologie de partage des accélérateurs hardwares pour les mêmes motifs de calcul. L’idée est donc de trouver dans les différentes applications parallèles exécutées par les différents processeurs des motifs de calcul communs. Ces motifs seront alors implantés sur le FPGA par un nombre réduit d’accélérateurs partagés entre les processeurs. Grâce à des modèles de programmation mixte, la méthodologie développée est capable de trouver, pour des performances exigés par le concepteur, le nombre optimal d’accélérateurs privés et/ou partagés pour les différents motifs. / No summary in english
95

Durcissement de circuits logiques reconfigurables / Hardening basic blocks in a mesh of clusters FPGA

Ben Dhia, Arwa 14 November 2014 (has links)
Avec les réductions d'échelle, les circuits électroniques deviennent de plus en plus petits, plus performants, consommant moins de puissance, mais aussi moins fiables. En effet, la fiabilité s'est récemment érigée en défi majeur dans l'industrie micro-électronique, devenant un critère de conception important, au même titre que la surface, la consommation de puissance et la vitesse. Par exemple, les défauts physiques dus aux imperfections dans le procédé de fabrication ont été observés plus fréquemment, affectant ainsi le rendement des circuits. Par ailleurs, les circuits nano-métriques deviennent pendant leur durée de vie plus vulnérables aux rayonnements ionisants, ce qui cause des fautes transitoires. Les défauts de fabrication, aussi bien que les fautes transitoires, diminuent la fiabilité des circuits intégrés. En avançant dans les nœuds technologiques, les circuits logiques programmables de type FPGA sont les premiers à entrer sur le marché, grâce à leur faible coût de développement et leur flexibilité qui leur permet d'être utilisés pour n'importe quelle application. Les FPGA possèdent des caractéristiques attrayantes, notamment pour les applications spatiales et aéronautiques, où la reconfigurabilité, les hautes performances et la faible consommation de puissance peuvent être exploitées pour développer des systèmes innovants. Néanmoins, les missions ont lieu dans un environnement rude, riche en radiations pouvant produire des erreurs soft dans les circuits électroniques. Ceci montre l'importance de la fiabilité des FPGA en tant que critère de conception dans les applications critiques. La plupart des FPGA commerciaux ont une architecture matricielle et leurs blocs logiques sont regroupés en clusters. Ainsi, cette thèse s'intéresse à la tolérance aux fautes des blocs de base ( blocs logiques élémentaires (BLE) et boîtes d'interconnexion ) dans un FPGA de type « matrice de clusters ». Dans le but d'améliorer la fiabilité de ces blocs, il est impératif de pouvoir d'abord l'évaluer, pour ensuite sélectionner la bonne technique de durcissement selon le budget mis à disposition. C'est bien le plan principal de cette thèse. Elle a essentiellement deux objectifs : (a) analyser la tolérance aux fautes des blocs de base dans un FPGA de type « matrice de clusters », et identifier les composants les plus vulnérables. (b) proposer des méthodes de durcissement à différents niveaux de granularité, en fonction du budget de durcissement. En ce qui concerne le premier objectif, une méthodologie pour évaluer la fiabilité du cluster a été proposée. Cette méthodologie emploie une méthode analytique déjà existante pour évaluer la fiabilité des circuits logiques combinatoires. La même méthode est utilisée pour identifier les blocs les plus éligibles au durcissement. Quant au deuxième objectif, des techniques de durcissement ont été proposées aux niveaux multiplexeur et transistor. Au niveau multiplexeur, deux solutions de durcissement ont été présentées. La première solution a recours à la redondance spatiale et concerne la structure du bloc logique. Une nouvelle architecture de BLE baptisée « Butterfly » est introduite. Elle a été comparée avec d'autres architectures de BLE en termes de fiabilité et de surcoût. La deuxième solution de durcissement est une technique dite « sans redondance ». Elle est basée sur une synthèse intelligente qui consiste à chercher la structure la plus fiable parmi toutes celles proposées dans la librairie du fondeur, avant d'utiliser directement de la redondance. Ensuite, au niveau transistor, de nouvelles architectures de multiplexeur, à sortie unique ou différentielles, ont été proposées. Elles ont été comparées à d'autres assemblages différents de transistors, selon des métriques de conception appropriées. / As feature sizes scale down to nano-design level, electronic devices have become smaller, more performant, less power-onsuming, but also less reliable. Indeed, reliability has arisen as a serious challenge in nowadays’ microelectronics industry and as an important design criterion, along with area, performance and power consumption. For instance, physical defects due to imperfections in the manufacturing process have been observed more frequently, impacting the yield. Besides, nanometric circuits have become more vulnerable during their lifetime to ionizing radiation which causes transient faults. Both manufacturing defects and transient faults contribute to decreasing reliability of integrated circuits. When moving to a new technology node, Field Programmable Gate Arrays (FPGAs) are the first coming into the market, thanks to their low development and Non-Recurring Engineering (NRE) costs and their flexibility to be used for any application. FPGAs have especially attractive characteristics for space and avionic applications, where reconfigurability, high performance and low-power consumption can be fruitfully used to develop innovative systems. However, missions take place in a harsh environment, rich in radiation, which can induce soft errors within electronic devices. This shows the importance of FPGA reliability as a design criterion in safety and critical applications. Most of commercial FPGAs have a mesh architecture and their logic blocks are gathered into clusters. Therefore, this thesis deals with the fault tolerance of basic blocks (clusters and switch boxes) in a mesh of clusters FPGA. These blocks are mainly made up of multiplexers. In order to improve their reliability, it is imperative to be able to assess it first, then select the proper hardening approach according to the available budget. So, this is the main outline in which this thesis is conceived. Its goals are twofold: (a) analyze the fault tolerance of the basic blocks in a mesh of clusters FPGA, and point out the most vulnerable components (b) propose hardening schemes at different granularity levels, depending on the hardening budget. As far as the first goal is concerned, a methodology to evaluate the reliability of the cluster is proposed. This methodology uses an existent analytical method for reliability computation of combinational circuits. The same method is employed to identify the worthiest components to be hardened. Regarding the second goal, hardening techniques are proposed at both multiplexer and transistor levels. At multiplexer level, two hardening solutions are presented. The first solution resorts to spacial redundancy and concerns the logic block structure. A novel Configurable Logic Block (CLB) architecture baptized Butterfly is introduced. It is compared with other hardened CLB architectures in terms of reliability and cost penalties. The second hardening solution is a redundanceless scheme. It is based on a “smart” synthesis that consists in seeking the most reliable design in a given founder library, instead of directly using a redundant solution. Then, at transistor level, new single-ended and dual-rail multiplexer architectures are proposed. They are compared to different other transistor structures, according to suitable design metrics.
96

Implementation of Logic Fault Tolerance on a Dynamically Reconfigurable FPGA

Jayarama, Kiran January 2016 (has links)
No description available.
97

THE IMPLEMENTATION OF AN IRREGULAR VITERBI TRELLIS DECODER

Lavin, Christopher 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The Viterbi algorithm has uses for both the decoding of convolutional codes and the detection of signals distorted by intersymbol interference (ISI). The operation of these processes is characterized by a trellis. An ARTM Tier-1 space-time coded telemetry receiver required the use of an irregular Viterbi trellis decoder to solve the dual antenna problem. The nature of the solution requires the trellis to deviate from conventional trellis structure and become time-varying. This paper explores the architectural challenges of such a trellis and presents a solution using a modified systolic array allowing the trellis to be realized in hardware.
98

Incorporating Physical Information into Clustering for FPGAs

Chen, Doris Tzu Lang January 2007 (has links)
The traditional approach to FPGA clustering and CLB-level placement has been shown to yield significantly worse overall placement quality than approaches which allow BLEs to move during placement. In practice, however, modern FPGA architectures require computationally-expensive Design Rule Checks (DRC) which render BLE-level placement impractical. This thesis research addresses this problem by proposing a novel clustering framework that produces better initial clusters that help to reduce the dependence on BLE-level placement. The work described in this dissertation includes: (1) a comparison of various clustering algorithms used for FPGAs, (2) the introduction of a novel hybridized clustering framework for timing-driven FPGA clustering, (3) the addition of physical information to make better clusters, (4) a comparison of the implemented approaches to known clustering tools, and (5) the implementation and evaluation of cluster improvement heuristics. The proposed techniques are quantified across accepted benchmarks and show that the implemented DPack produces results with 16% less wire length, 19% smaller minimum channel widths, and 8% less critical delay, on average, than known academic tools. The hybridized approach, HDPack, is found to achieve 21% less wire length, 24% smaller minimum channel widths, and 6% less critical delay, on average.
99

Dynamic partial reconfiguration management for high performance and reliability in FPGAs

Ebrahim, Ali January 2015 (has links)
Modern Field-Programmable Gate Arrays (FPGAs) are no longer used to implement small “glue logic” circuitries. The high-density of reconfigurable logic resources in today’s FPGAs enable the implementation of large systems in a single chip. FPGAs are highly flexible devices; their functionality can be altered by simply loading a new binary file in their configuration memory. While the flexibility of FPGAs is comparable to General-Purpose Processors (GPPs), in the sense that different functions can be performed using the same hardware, the performance gain that can be achieved using FPGAs can be orders of magnitudes higher as FPGAs offer the ability for customisation of parallel computational architectures. Dynamic Partial Reconfiguration (DPR) allows for changing the functionality of certain blocks on the chip while the rest of the FPGA is operational. DPR has sparked the interest of researchers to explore new computational platforms where computational tasks are off-loaded from a main CPU to be executed using dedicated reconfigurable hardware accelerators configured on demand at run-time. By having a battery of custom accelerators which can be swapped in and out of the FPGA at runtime, a higher computational density can be achieved compared to static systems where the accelerators are bound to fixed locations within the chip. Furthermore, the ability of relocating these accelerators across several locations on the chip allows for the implementation of adaptive systems which can mitigate emerging faults in the FPGA chip when operating in harsh environments. By porting the appropriate fault mitigation techniques in such computational platforms, the advantages of FPGAs can be harnessed in different applications in space and military electronics where FPGAs are usually seen as unreliable devices due to their sensitivity to radiation and extreme environmental conditions. In light of the above, this thesis investigates the deployment of DPR as: 1) a method for enhancing performance by efficient exploitation of the FPGA resources, and 2) a method for enhancing the reliability of systems intended to operate in harsh environments. Achieving optimal performance in such systems requires an efficient internal configuration management system to manage the reconfiguration and execution of the reconfigurable modules in the FPGA. In addition, the system needs to support “fault-resilience” features by integrating parameterisable fault detection and recovery capabilities to meet the reliability standard of fault-tolerant applications. This thesis addresses all the design and implementation aspects of an Internal Configuration Manger (ICM) which supports a novel bitstream relocation model to enable the placement of relocatable accelerators across several locations on the FPGA chip. In addition to supporting all the configuration capabilities required to implement a Reconfigurable Operating System (ROS), the proposed ICM also supports the novel multiple-clone configuration technique which allows for cloning several instances of the same hardware accelerator at the same time resulting in much shorter configuration time compared to traditional configuration techniques. A faulttolerant (FT) version of the proposed ICM which supports a comprehensive faultrecovery scheme is also introduced in this thesis. The proposed FT-ICM is designed with a much smaller area footprint compared to Triple Modular Redundancy (TMR) hardening techniques while keeping a comparable level of fault-resilience. The capabilities of the proposed ICM system are demonstrated with two novel applications. The first application demonstrates a proof-of-concept reliable FPGA server solution used for executing encryption/decryption queries. The proposed server deploys bitstream relocation and modular redundancy to mitigate both permanent and transient faults in the device. It also deploys a novel Built-In Self- Test (BIST) diagnosis scheme, specifically designed to detect emerging permanent faults in the system at run-time. The second application is a data mining application where DPR is used to increase the computational density of a system used to implement the Frequent Itemset Mining (FIM) problem.
100

Design and Implementation of an Universal Lattice Decoder on FPGA

Kura, Swapna 20 May 2005 (has links)
In wireless communication, MIMO (multiple input multiple output) is one of the promising technologies which improves the range and performance of transmission without increasing the bandwidth, while providing high rates. High speed hardware MIMO decoders are one of the keys to apply this technology in applications. In order to support the high data rates, the underlying hardware must have significant processing capabilities. FPGA improves the speed of signal processing using parallelism and reconfigurability advantages. The objective of this thesis is to develop an efficient hardware architectural model for the universal lattice decoder and prototype it on FPGA. The original algorithm is modified to ensure the high data rate via taking the advantage of FPGA features. The simulation results of software, hardware are verified and the BER performance of both the algorithms is estimated. The system prototype of the decoder with 4-transmit and 4-receive antennas using a 4-PAM (Pulse amplitude modulation) supports 6.32 Mbit/s data rate for parallelpipeline implementation on FPGA platform, which is about two orders of magnitude faster than its DSP implementation.

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