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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.
41

A New Approach to the Decomposition of Incompletely Specified Functions Based on Graph Coloring and Local Transformation and Its Application to FPGA Mapping

Wan, Wei 08 May 1992 (has links)
The thesis presents a new approach to the decomposition of incompletely specified functions and its application to FPGA (Field Programmable Gate Array) mapping. Five methods: Variable Partitioning, Graph Coloring, Bond Set Encoding, CLB Reusing and Local Transformation are developed in order to efficiently perform decomposition and FPGA (Lookup-Table based FPGA) mapping. 1) Variable Partitioning is a high quality hemistic method used to find the "best" partitions, avoiding the very time consuming testing of all possible decomposition charts, which is impractical when there are many input variables in the input function. 2) Graph Coloring is another high quality heuristic\ used to perform the quasi-optimum don't care assignment, making the program possible to accept incompletely specified function and perform a quasi-optimum assignment to the unspecified part of the function. 3) Bond Set Encoding algorithm is used to simplify the decomposed blocks during the process of decomposition. 4) CLB Reusing algorithm is used to reduce the number of CLBs used in the final mapped circuit. 5) Local Transformation concept is introduced to transform nondecomposable functions into decomposable ones, thus making it possible to apply decomposition method to FPGA mapping. All the above developed methods are incorporated into a program named TRADE, which performs global optimization over the input functions. While most of the existing methods recursively perform local optimization over some kinds of network-like graphs, and few of them can handle incompletely specified functions. Cube calculus is used in the TRADE program, the operations are global and very fast. A short description of the TRADE program and the evaluation of the results are provided at the_ end of the thesis. For many benchmarks the TRADE program gives better results than any program published in the literature.
42

The Design, Realization and Testing of the ILU of the CCM2 Using FPGA Technology

Foote, David W. 09 June 1994 (has links)
Most existing computers today are built upon a subset of the arithmetic system which is based upon the foundation of set theory. All formal systems can be expressed in terms of arithmetic and logic on current arithmetic computers through an appropriate model, then work with the model using software manipulation. However, severe speed degradation is the price one must pay for using a software-based approach, making several high-level formal systems impractical. To improve the speed at which computers can implement these high-level systems, one must either design special hardware, implementing specific operations much like math and image processing coprocessors, or execute operations upon multiple processors in a parallel fashion. Due to the increase in developing applications for the manipulation of logic functions, an interest in the logic machine has arisen. Many applications such as logic optimization, simulation, pattern recognition and image processing can be better implemented with a logic machine. This thesis proposes the design, hardware realization, and testing of the iterative logic unit (ILU) of the Cube Calculus Machine II (CCM2). The CCM2 is a general purpose computer with an architecture that emphasizes a data path designed to execute operations of cube calculus, a popular algebraic model used in the minimization of Boolean functions. The ILU is an iterative logic array of cells (ITs) using internal distributed control, enabling the execution of basic cube operations, while the Control Unit (CU) handles global signals from the host computer. The ILU of the CCM2 has been realized in hardware using Xilinx Logic Cell Arrays (LCAs). FPGAs offer the logic density and versatility of gate arrays, with the off-the shelf availability and time-to-market advantages of standard user-programmable devices. These devices can be reconfigured, allowing multiple revisions and future design generations to accommodate the same device, thus saving design and production costs, an ideal solution to the resource and financial problems plaguing the University environment.
43

Minimization of Permuted Reed-Muller Trees and Reed-Muller Trees for Cellular Logic Programmable Gate Arrays

Wu, Lifei 09 February 1993 (has links)
The new family of Field Programmable Gate Arrays, CLI 6000 from Concurrent Logic Inc realizes truly Cellular Logic. It has been mainly designed for the realization of data path architectures. However, the realizable logic functions provided by its macrocells and their limited connectivity call also for new general-purpose logic synthesis methods. The basic cell of CLi 6000 can be programmed to realize a two-input multiplexer ( A*B + C*B ), an AND/EXOR cell ( A*B Ea C ), or the basic 2-input AND, OR and EXOR gate. This suggests to using these cells for tree-like expansions. These "cellular logic" devices require regular connection patterns in the netlists resulting from logic synthesis. This thesis presents a synthesis tree searching program PROMPT, which generates AND/EXOR tree circuits from given Boolean functions. Such circuits have the property that the gate structures are AND/EXOR ( A *B EB C ), AND and EXOR which could be realized by the CLI6000 cells. Also, the connection. way in the circuit is that usually the output of one level gate is the input of the next level gate of the tree. This matches ideally to the architecture of the CLI6000 bussing network where the macrocells have only connections to their neighboring cells. PROMPT is based on the Davio expansions ( an equivalent of the Shannon expansions for the EXOR gates ) as its Boolean decomposition methods. The program includes three versions: exact version, heuristic version and fixed-variable version. The exact version of PROMPT generates the Permuted Reed-Muller Tree circuit which has the minimum number of gates. Such tree circuit is obtained by searching through all possible combinations of the expansion variable orders to get the one which needs the least number of gates. The heuristic version of PROMPT is designed to decrease the time complexity of the search algorithm when dealing with logic functions having many input variables. It generates a Permuted Reed-Muller Tree which may not have the minimum number of gates. However, the tree searching time in this version decreases tremendously compared to the time necessary in the exact version. The fix-variable version is developed to generate Reed-Muller Tree circuits. Such circuits will have the same expansion variables at the same tree level, so they can be easier routed after the placement to the CLI6000 chips. In short, the program PROMPT generates the PRM and RM tree circuits which are particularly well matched to both the realization of logic cell and connection structure of the CLI6000 device. Thus, the PRM and RM circuits can be easily placed and routed on the CLI6000 FPGAs.
44

Modernisering av marint styr- och övervakningsskåp

Oskarsson, Daniel, Henriksson, Jan-Erik January 2003 (has links)
No description available.
45

Implementering av styrgränssnitt mellan leksaksstridsvagn och digital signalprocessor / Implementation of a Control Interface Between a Toy Tank and a Digital Signal Processor

Östlund, Anders, Suneson, Tor January 2007 (has links)
<p>Denna rapport omfattar ett 15 poängs (22,5 högskolepoäng) examensarbete vid Karlstads universitet. Arbetet har utförts på plats hos BAE Systems Bofors i Karlskoga. Företaget ville kunna styra en radiostyrd leksaksstridsvagn med en laserpekare. En kamera ansluten till en digital signalprocessor (DSP) skulle kunna detektera var en laserpunkt befinner sig och styra stridsvagnen mot den.</p><p>Ett styrgränssnitt mellan DSP:n och leksaksstridsvagnen konstruerades och byggdes med hjälp av en programmerbar logisk krets. Leksaksstridsvagnens interna signalsystem analyserades. En manchesterkodad signal i form av ett 32-bitars seriellt kodord hittades, vilket ursprungligen kom från radiostyrningen. Ett styrgränssnitt konstruerades kring en CPLD (Complex Programmable Logic Device) vilken programmerades med VHDL (Very high speed integrated Hardware Description Language) som återskapar den Manchesterkodade styrsignalen.</p><p>Gränssnittet ansluter till DSP:n som kontrollerar stridsvagnens styrning och övriga funktioner till fullo. Kommunikationen mellan styrgränssnittet och DSP:n sker via ett parallellgränssnitt som är 16-bitar brett. 13 bitar är datasignaler och övriga tre är ”styrbitar” som konfigurerar gränssnittet. En applikation integrerades i projektet för att demonstrera styrgränssnittets funktion. DSP:n tolkar var en laserpunkt befinner sig inom ett kameraområde och skickar motsvarande styrsignaler till leksaksstridsvagnen.</p> / <p>This report consists of a 15 points (22.5 ECTS) Exam Degree project at Karlstad University. The work was done on location at BAE Systems Bofors AB in Karlskoga. The company wanted to control a radio controlled toy tank from a digital signal processor (DSP). A camera connected to the DSP locates the laser point and steers the toy tank towards it.</p><p>An interface using a programmable logic device was constructed that connects the DSP to the toy tank. The internal signals in the toy tank was analyzed and a Manchester coded signal in form of a 32-bit serial code word was detected. The code word originated from the radio controller. The control interface was built around a CPLD (Complex Programmable Logic Device) which was programmed in VHDL (Very high speed integrated Hardware Description Language). The control interface recreates the signal controlling the toy tank.</p><p>The interface connects the toy tank to the DSP which controls the toy tank and it’s functions to the full extent. Communication between the interface and the DSP is done via a 16 bit parallel connection. 13 of the bits are data bits and the remaining 3 are control bits that are used to set up the interface. An application was integrated in the project where the DSP is detecting a laser point. Corresponding signals to the laser points position where sent to the control interface to demonstrate the function of the interface.</p>
46

Hardware accelerators for embedded fingerprint-based personal recognition systems

Fons Lluís, Mariano 29 May 2012 (has links)
Abstract The development of automatic biometrics-based personal recognition systems is a reality in the current technological age. Not only those operations demanding stringent security levels but also many daily use consumer applications request the existence of computational platforms in charge of recognizing the identity of one individual based on the analysis of his/her physiological and/or behavioural characteristics. The state of the art points out two main open problems in the implementation of such applications: on the one hand, the needed reliability improvement in terms of recognition accuracy, overall security and real-time performances; and on the other hand, the cost reduction of those physical platforms in charge of the processing. This work aims at finding the proper system architecture able to address those limitations of current personal recognition applications. Embedded system solutions based on hardware-software co-design techniques and programmable (and run-time reconfigurable) logic devices under FPGAs or SOPCs is proven to be an efficient alternative to those existing multiprocessor systems based on HPCs, GPUs or PC platforms in the development of that kind of high-performance applications at low cost / El desenvolupament de sistemes automàtics de reconeixement personal basats en tècniques biomètriques esdevé una realitat en l’era tecnològica actual. No només aquelles operacions que exigeixen un elevat nivell de seguretat sinó també moltes aplicacions quotidianes demanen l’existència de plataformes computacionals encarregades de reconèixer la identitat d’un individu a partir de l’anàlisi de les seves característiques fisiològiques i/o comportamentals. L’estat de l’art de la tècnica identifica dues limitacions importants en la implementació d’aquest tipus d’aplicacions: per una banda, és necessària la millora de la fiabilitat d’aquests sistemes en termes de precisió en el procés de reconeixement personal, seguretat i execució en temps real; i per altra banda, és necessari reduir notablement el cost dels sistemes electrònics encarregats del processat biomètric. Aquest treball té per objectiu la cerca de l’arquitectura adequada a nivell de sistema que permeti fer front a les limitacions de les aplicacions de reconeixement personal actuals. Es demostra que la proposta de sistemes empotrats basats en tècniques de codisseny hardware-software i dispositius lògics programables (i reconfigurables en temps d’execució) sobre FPGAs o SOPCs resulta ser una alternativa eficient en front d’aquells sistemes multiprocessadors existents basats en HPCs, GPUs o plataformes PC per al desenvolupament d’aquests tipus d’aplicacions que requereixen un alt nivell de prestacions a baix cost. / El desarrollo de sistemas automáticos de reconocimiento personal basados en técnicas biométricas se ha convertido en una realidad en la era tecnológica actual. No tan solo aquellas operaciones que requieren un alto nivel de seguridad sino también muchas otras aplicaciones cotidianas exigen la existencia de plataformas computacionales encargadas de verificar la identidad de un individuo a partir del análisis de sus características fisiológicas y/o comportamentales. El estado del arte de la técnica identifica dos limitaciones importantes en la implementación de este tipo de aplicaciones: por un lado, es necesario mejorar la fiabilidad que presentan estos sistemas en términos de precisión en el proceso de reconocimiento personal, seguridad y ejecución en tiempo real; y por otro lado, es necesario reducir notablemente el coste de los sistemas electrónicos encargados de dicho procesado biométrico. Este trabajo tiene por objetivo la búsqueda de aquella arquitectura adecuada a nivel de sistema que permita hacer frente a las limitaciones de los sistemas de reconocimiento personal actuales. Se demuestra que la propuesta basada en sistemas embebidos implementados mediante técnicas de codiseño hardware-software y dispositivos lógicos programables (y reconfigurables en tiempo de ejecución) sobre FPGAs o SOPCs resulta ser una alternativa eficiente frente a aquellos sistemas multiprocesador actuales basados en HPCs, GPUs o plataformas PC en el ámbito del desarrollo de aplicaciones que demandan un alto nivel de prestaciones a bajo coste
47

Modernisering av marint styr- och övervakningsskåp

Oskarsson, Daniel, Henriksson, Jan-Erik January 2003 (has links)
No description available.
48

The Distributed Control Program Generator of Microprocessor-based Environment

Huang, Szu-kai 30 July 2012 (has links)
In the field of the industrial automatic control, both MCU (Micro Control Unit) and PLC (Programmable Logic Controller) are widely being used in DCS (Distributed Control System). Since MCU can provide complex process scheduling, accurate timing control and PLC has the advantages of easy programming and maintaining. However, the control programs of the MCU are hard to design and maintain. Identically, the poor signal processing ability, high cost and the restrictive functions are the major defects of PLC. In order to solve the drawbacks described above in MCU and PLC, we provide a PLC-like interface for users to access the devices and set the registers of MCU. Likewise, designers can develop the control program via Event-table-driven modules. On the other hand, our main goal of DCS is to quickly construct the distributed N level network topology based on Modbus protocol, which is efficient and reliable. Therefore, we bring up a data collection method and Slave-to-Slave strategy so as to distribute the master loading, reduce the package transmission times and improve the real-time latency. In conclusion, our research results not only congregate the benefits of MCU and PLC but provide an environment to quickly construct and conveniently monitor DCS, which meets the time-to-market demands.
49

Design and implementation of a sub-threshold wireless BFSK transmitter

Paul, Suganth 15 May 2009 (has links)
Power Consumption in VLSI (Very Large Scale Integrated) circuits is currently a major issue in the semiconductor industry. Power is a first order design constraint in many applications. Several of these applications need extreme low power but do not need high speed. Sub-threshold circuit design can be used in these cases, but at such a low supply voltage these circuits exhibit an exponential sensitivity to process, voltage and temperature (PVT) variations. In this thesis we implement and test a robust sub-threshold design flow which uses circuit level PVT compensation to stabilize circuit performance. This is done by dynamic modulation of the delay of a representative signal in the circuit and then phase locking it with an external reference signal. We design and fabricate a sub-threshold wireless BFSK transmitter chip. The transmitter is specified to transmit baseband signals up to a data rate of 32kbps over a distance of 1000m. In addition to the sub-threshold implementation, we implement the BFSK transmitter using a standard cell methodology on the same die operating at super-threshold voltages on a different voltage domain. Experiments using the fabricated die show that the sub-threshold circuit consumes 19.4x lower power than the traditional standard cell based implementation.
50

Design and implementation of a sub-threshold wireless BFSK transmitter

Paul, Suganth 10 October 2008 (has links)
Power Consumption in VLSI (Very Large Scale Integrated) circuits is currently a major issue in the semiconductor industry. Power is a first order design constraint in many applications. Several of these applications need extreme low power but do not need high speed. Sub-threshold circuit design can be used in these cases, but at such a low supply voltage these circuits exhibit an exponential sensitivity to process, voltage and temperature (PVT) variations. In this thesis we implement and test a robust sub-threshold design flow which uses circuit level PVT compensation to stabilize circuit performance. This is done by dynamic modulation of the delay of a representative signal in the circuit and then phase locking it with an external reference signal. We design and fabricate a sub-threshold wireless BFSK transmitter chip. The transmitter is specified to transmit baseband signals up to a data rate of 32kbps over a distance of 1000m. In addition to the sub-threshold implementation, we implement the BFSK transmitter using a standard cell methodology on the same die operating at super-threshold voltages on a different voltage domain. Experiments using the fabricated die show that the sub-threshold circuit consumes 19.4x lower power than the traditional standard cell based implementation.

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