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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.
301

Evaluation of GNU Radio Platform Enhanced for Hardware Accelerated Radio Design

Karve, Mrudula Prabhakar 05 January 2011 (has links)
The advent of software radio technology has enabled radio developers to design and implement radios with great ease and flexibility. Software radios are effective in experimentation and development of radio designs. However, they have limitations when it comes to high-speed, high-throughput designs. This limitation can be overcome by introducing a hardware element to the software radio platform. Enhancing GNU Radio for Hardware Accelerated Radio Design project implements such a scheme by augmenting an FPGA co-processor to a conventional GNU Radio flow. In this thesis, this novel platform is evaluated in terms of performance of a radio design, as well as hardware and software system requirements. A simple and efficient Zigbee receiver design is presented. Implementation of this receiver is used as a proof-of-concept for the effectiveness and design methodology of the modified GNU Radio. This work also proposes a scheme to extend this idea for design of ultra-wideband radio systems based on multiband-OFDM. / Master of Science
302

An FPGA-Based Multiuser Receiver Employing Parallel Interference Cancellation

Swanchara, Steven F. 17 September 1998 (has links)
Research efforts have shown that capacity in a DS/CDMA cellular system can be increased through the use of digital signal processing techniques that exploit the nature of the multiple access interference (MAI). By jointly demodulating the users in the system, this interference can be characterized and reduced thus decreasing the overall probability of error in the system. Numerous multiuser structures exist, each with varying degrees of complexity and performance. However, the size and complexity of these structures is large relative to a conventional receiver. This effort demonstrates a practical approach to implementing parallel interference cancellation applied to DBPSK DS/CDMA on an FPGA-based configurable computing platform. The system presented acquires, tracks, cancels, and demodulates four users independently and performs various levels of interference cancellation. The performance gain of the receiver in a four-user environment under various levels of noise and cancellation are presented. / Master of Science
303

A Secure Software Platform for Real-Time Embedded Systems

Lorden, Eric James 09 January 2007 (has links)
Embedded systems are becoming nearly ubiquitous, found in a plurality of devices ranging from everyday cars and dishwashers to sophisticated spy satellites and remote sensing equipment. As the applications for embedded systems increase in number and diversity and continue to pervade our lives, a need arises to secure these systems. Whether the need arises from a desire to protect personal, proprietary, sensitive, or classified information, the security of the embedded system seeks to maintain the confidentiality and integrity of data contained within the system. Research into securing embedded systems is in its nascent stages. The generally accepted methodology of securing embedded systems involves techniques that either modify an embedded system's processor or entail custom ASIC hardware. This thesis presents a novel embedded system architecture for secure software processing that does not involve processor modification, but rather processor augmentation to ensure the confidentiality and integrity of information contained within the embedded system. Specifically, configurable logic placed at the processor periphery provides just-in-time cryptographic transformation of instructions, data, and I/O of a running embedded application. In addition to presenting the embedded secure software platform, this thesis provides a characterization of the data protection architecture of the platform. / Master of Science
304

A Self-Reconfiguring Platform For Embedded Systems

Leon, Santiago Andres 24 August 2001 (has links)
The JBits Application Programming Interface has significantly shortened FPGA reconfiguration times by manipulating the configurable resources of the FPGAs directly under software control. The execution of JBits programs, however, requires a Java Virtual Machine to be implemented on the platform where the configurations will be modified. This presents a problem for embedded systems where a microprocessor to run a Java Virtual Machine may not be available or desirable. This thesis discusses the implementation of a FPGA platform that allows the execution of JBits programs, effectively changing the configuration of a FPGA within a FPGA. This thesis also presents a four step developing and testing strategy for JBits programs that are intended to run on this FPGA platform. / Master of Science
305

An Analysis of an Interrupt-Driven Implementation of the Master-Worker Model with Application-Specific Coprocessors

Hickman, Joseph 17 January 2008 (has links)
In this thesis, we present a versatile parallel programming model composed of an individual general-purpose processor aided by several application-specific coprocessors. These computing units operate under a simplification of the master-worker model. The user-defined coprocessors may be either homogeneous or heterogeneous. We analyze system performance with regard to system size and task granularity, and we present experimental results to determine the optimal operating conditions. Finally, we consider the suitability of this approach for scientific simulations — specifically for use in agent-based models of biological systems. / Master of Science
306

FIR implementation on FPGA: investigate the FIR order on SDA and PDA algorithms

Migdadi, Hassan S.O., Abd-Alhameed, Raed, Obeidat, Huthaifa A.N., Noras, James M., Qaralleh, E.A.A., Ngala, Mohammad J. January 2015 (has links)
No / Finite impulse response (FIR) digital filters are extensively used due to their key role in various digital signal processing (DSP) applications. Several attempts have been made to develop hardware realization of FIR filters characterized by implementation complexity, precision and high speed. Field Programmable Gate Array is a reconfigurable realization of FIR filters. Field-programmable gate arrays (FPGAs) are on the verge of revolutionizing digital signal processing. Many front-end digital signal processing (DSP) algorithms, such as FFTs, FIR or IIR filters, are now most often realized by FPGAs. Modern FPGA families provide DSP arithmetic support with fast-carry chains that are used to implement multiply-accumulates (MACs) at high speed, with low overhead and low costs. In this paper, distributed arithmetic (DA) realization of FIR filter as serial and parallel are discussed in terms of hardware cost and resource utilization.
307

System design of an ATM over satellite interconnect device

Pan, Kongfan 01 July 2000 (has links)
No description available.
308

Using FPGAs to perform embedded image registration

White, Brandyn A. 01 January 2009 (has links)
Image registration is the process of relating the intensity values of one image to another image using their pixel c~?tent alone. An example use of this technique is to create panoramas from individual images taken froin a rotating camera. A class of image registration algorithms, known as direct registration methods, uses intensity derivatives to iteratively estimate the parameters modeling the transformation between the images. Direct methods are known for their sub-pixel accurate results; however, their execution is computationally expensive, often times preventing use in an embedded capacity like those encountered in small UIUllann~d aerial vehicle or mobile phone applications. In this work, a high performance FPGA-based direct affine image registration core is presented. The proposed method combines two features: a fully pipelined architecture to compute the linear system of equations, and a Gaussian elimination module, implemented as a finite state machine, to solve the resulting linear system. The design is implemented on a Xilinx ML506 development board featuring a Virtex-5 SX50 FPGA, zero bus turn-around (ZBT) RAM, and VGA input. Experimentation is performed on both real and synthetic data. The registration core performs in excess of 80 frames per second on 640x480 images using one registration iteration.
309

VHDL design of computer vision tasks

Phillips, Walter 01 January 2001 (has links)
Field Programmable Gate Arrays (FPGAs) offer a new opportunity for computer vision algorithms. By implementing in Very High Speed Integrated Circuit Hardware Description languate (VHDL), algorithms can be developed quickly, while being running much faster than by using conventional Von Neumann machines (such as a Personal Computer or Macintosh). The process of creating a working design from an algorithm is described in detail, and we present experimental results obtained from such a process for Sobel edge detection, as well as modifications for techniques for background modeling and fire detection.
310

On the Programmability and Performance of OpenCL Designs for FPGA

Verma, Anshuman 09 February 2018 (has links)
Field programmable gate arrays (FPGAs) have been emerging as a promising bedrock to provide opportunities for several types of accelerators that spans across various domains such as finance, web-search, and data center networking, among others. Research interests facilitating the development of accelerators on FPGAs are increasing significantly, in particular, because of their effectiveness with a variety of applications, flexibility, and high performance per watt. However, several key challenges remain that hinder their large-scale deployment. Overcoming these challenges would enable them to match the pervasiveness of graphics processor units (GPUs), their principal competitors in this arena. One of the primary reasons responsible for the slow adaptation by programmers has been the programming model, which uses a low-level hardware description language (HDL). Using HDLs require a detailed understanding of logic design and significant effort to implement and verify the behavioral models, with the latter growing with its complexity. Recent advancements in high-level language synthesis (HLS) tools have addressed this challenge to a considerable extent by allowing the programmers to write their applications in a high-level language named OpenCL. These applications are then compiled and synthesized to create a bitstream that configures the FPGA. This thesis characterizes the efficacy of HLS compiler optimizations that can be employed to improve the performance of these applications. The synthesized hardware from OpenCL kernels is fundamentally different from traditional hardware such as CPUs and GPUs, which exploit instruction level parallelism (ILP) thread level parallelism (TLP), or data level parallelism (DLP) for performance gains. FPGAs typically use deep pipelining (i.e., ILP) for performance. A stall in this pipeline may severely undermine the performance of applications. Thus, it is imperative to identify and remove any such bottlenecks. To this end, this thesis presents and discusses a software-centric framework to debug and profile the synthesized designs generated using HLS tools. This thesis proposes basic code patterns, including a timestamp and a scalable framework, which can be plugged easily into OpenCL kernels, to collect and process run-time information dynamically. This scalable framework has a small overhead for area utilization and frequency but provides fine-grained information about the bottlenecks and latencies in design. Additionally, although HLS tools have improved programmability, this may come at the cost of performance or area utilization. This thesis addresses this design trade-off via a comparative study of a hand-coded design in HDL and an architecturally similar, tool-generated design using an OpenCL compiler in the application area of 3D-stencil (i.e., structured grid) computation. Experiments in this thesis show that the performance of an OpenCL approach can achieve 95% of the peak attainable performance of a microkernel for multiple problem sizes. In comparison to the OpenCL approach, an HDL approach results in approximately 50% less memory usage and only 2% better performance on average. / MS / A hardware chip consists of switches or transistors, and a modern chip can have a few billions of them. Specifying the interconnection among these transistors and their placement on a chip is a complex problem. To simplify this, the chip-design flow uses automated tools and abstraction at the different levels of the flow, such as architecture, design, synthesis, placement, among others. During design, an engineer specifies the behavioral model in a hardware description language (HDL), which is later used by the automated tools for further processing. Using the HDL requires a detailed understanding of logic design and significant effort to implement and verify the behavioral models, with the latter growing with its complexity. Recent advancements in high-level language synthesis tools have addressed this challenge to a considerable extent by allowing the programmers to write their applications in a high-level language. This thesis characterizes the efficacy of such a tool and available optimizations that can be employed to improve the performance of these applications. Additionally, this thesis presents and discusses a framework to debug and profile the designs generated using high-level synthesis tools, which can be plugged easily into an application, to collect and process run-time information dynamically. This scalable framework has a small overhead but provides fine-grained information about the bottlenecks in the design. Furthermore, the experiments in this work show that a design generated from a high-level synthesis tool has similar performance when compared to a manual design in HDL, at the expense of area utilization.

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