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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.
111

Sound Level Measurement System

Johansson, Tore January 2006 (has links)
The purpose of this master thesis work is to design a device that measures the loudness of sound for different frequencies. This device is divided in three parts; a microphone that captures the sound, one A/D converter that samples the sound and one FPGA which analyse the data using an FFT algorithm. LEDs connected to the FPGA are used to indicate different output levels. A db(A) filter is applied that weights each frequency, before the different outputlevels are measured for each frequency. This system is supposed to be a subsystem to a larger system that is developed in a company. However, because of the risk that competitors might be able to guess the next product move of the company, the company is anonymous in this report. All the components used are paid for by the company and in return the company gets an idea of the complexity of the system and a basis for future design decisions.
112

FPGA-Based Lossless Data Compression Using GNU Zip

Rigler, Suzanne 20 January 2007 (has links)
Lossless data compression algorithms are widely used by data communication systems and data storage systems to reduce the amount of data transferred and stored. GNU Zip (GZIP) [1] is a popular compression utility that delivers reasonable compression ratios without the need for exploiting patented compression algorithms [2, 3]. The compression algorithm in GZIP uses a variation of LZ77 encoding, static Huffman encoding and dynamic Huffman encoding. Given the fact that web traffic accounts for 42% [4] of all internet traffic, the acceleration of algorithms like GZIP could be quite beneficial towards reducing internet traffic. A hardware implementation of the GZIP algorithm could be used to allow CPUs to perform other tasks, thus boosting system performance. This thesis presents a hardware implementation of GZIP encoder written in VHDL. Unlike previous attempts to design hardware-based encoders [5, 6], the design is compliant with GZIP specification and includes all three of the GZIP compression modes. Files compressed in hardware can be decompressed with the software version of GZIP. The flexibility of the design allows for hardware-based implementations using either FPGAs or ASICs. The design has been prototyped on an Altera DE2 Educational Board. Data is read and stored using an on board SD Card reader implemented in NIOS II processor. The design utilizes 20 610 LEs, 68 913 memory bits, and the on board SRAM, and the SDRAM to implement a fully functional GZIP encoder.
113

Hardware Implementation of Fast Fourier Transform

Tsai, Hung-Chieh 20 July 2005 (has links)
In this thesis, an FFT (Fast Fourier Transform) hardware circuit is designed for OFDM systems. A new memory table permutation deletion method, which can reduce the size of memory storing twiddle factors table, is proposed. The architecture of the FFT circuit is based on the faster split-radix algorithm with SDF (Single-path Delay Feedback) pipeline structure. The bits number of the signal is carefully selected by system simulation to meet the system requirements. Based on the simulation results, a small area FFT circuit is carried out for OFDM systems.
114

CORDIC-Based Signed-bit Predictable SIN-COS Generator And It¡¦s FPGA Implementation

Chao-Chuan, Huang 03 August 2000 (has links)
In this paper, we propose an area-time efficient design for redundant CORDIC-based SIN/COS evaluation by predict on the polarity of micro-rotations using a novel technique called ¡§Base Transfer angle Decomposition Algorithm¡¨(BTDA). The proposed design benefits from a constant scaling and requires no correcting iterations. By predicting the polarity of the signed bit of the micro-rotation, the critical paths of the unfolded and the pipelined designs involve only the X and Y recurrences. The implementations of BTDA architectures for 24-bit wide CORDIC-Base SIN/COS generator were synthesized using FPGA tools (XILINX Foundation Series version 2.1i), and the area-time complexities are presented for unfolded as well as pipelined designs. The proposed design results save more than 25% hardware area with speed-up of more than 30% compared with the exiting methods. Keywords: CORDIC, BTDA, Redundant, SIN/COS, FPGA
115

Multiple personality integrated circuits and the cost of programmability

York, Johnathan Andrew 11 July 2012 (has links)
This dissertation explores the cost of programmability in computing devices as measured relative to fixed-function devices implementing the same functionality using the same physical fabrication technology. The central claim elevates programmability to an explicit design parameter that (1) can be rigorously defined, (2) has measurable costs amenable to high-level modeling, (3) yields a design-space with distinct regions and properties, and (4) can be usefully manipulated using computer-aided design tools. The first portion of the the work is devoted to laying a rigorous logical foundation to support both this and future work on the subject. The second portion supports the thesis within this established logical foundation, using a specific engineering problem as a narrative vehicle. The engineering problem explored is that of mechanically adding a useful degree of programmability into preexisting fixed-function logic while minimizing the added overhead. Varying criteria for usefulness are proposed and the relative costs estimated both analytically and through case-study using standard-cell logic synthesis. In the case study, a methodology for the automatic generation of reconfigurable logic highly optimized for a specific set of computing applications is demonstrated. The approach stands in contrast to traditional reconfigurable computing techniques which focus on providing general purpose functionality at the expense of substantial overheads relative to fixed-purpose implementations. / text
116

Acceleration of Multi-agent Simulation on FPGAs

Cui, Lintao Unknown Date
No description available.
117

Compact and accurate hardware simulation of wireless channels for single and multiple antenna systems

Fouladi Fard, Saeed Unknown Date
No description available.
118

Dynamically and partially reconfigurable hardware architectures for high performance microarray bioinformatics data analysis

Hussain, Hanaa Mohammad January 2012 (has links)
The field of Bioinformatics and Computational Biology (BCB) is a multidisciplinary field that has emerged due to the computational demands of current state-of-the-art biotechnology. BCB deals with the storage, organization, retrieval, and analysis of biological datasets, which have grown in size and complexity in recent years especially after the completion of the human genome project. The advent of Microarray technology in the 1990s has resulted in the new concept of high throughput experiment, which is a biotechnology that measures the gene expression profiles of thousands of genes simultaneously. As such, Microarray requires high computational power to extract the biological relevance from its high dimensional data. Current general purpose processors (GPPs) has been unable to keep-up with the increasing computational demands of Microarrays and reached a limit in terms of clock speed. Consequently, Field Programmable Gate Arrays (FPGAs) have been proposed as a low power viable solution to overcome the computational limitations of GPPs and other methods. The research presented in this thesis harnesses current state-of-the-art FPGAs and tools to accelerate some of the most widely used data mining methods used for the analysis of Microarray data in an effort to investigate the viability of the technology as an efficient, low power, and economic solution for the analysis of Microarray data. Three widely used methods have been selected for the FPGA implementations: one is the un-supervised Kmeans clustering algorithm, while the other two are supervised classification methods, namely, the K-Nearest Neighbour (K-NN) and Support Vector Machines (SVM). These methods are thought to benefit from parallel implementation. This thesis presents detailed designs and implementations of these three BCB applications on FPGA captured in Verilog HDL, whose performance are compared with equivalent implementations running on GPPs. In addition to acceleration, the benefits of current dynamic partial reconfiguration (DPR) capability of modern Xilinx’ FPGAs are investigated with reference to the aforementioned data mining methods. Implementing K-means clustering on FPGA using non-DPR design flow has outperformed equivalent implementations in GPP and GPU in terms of speed-up by two orders and one order of magnitude, respectively; while being eight times more power efficient than GPP and four times more than a GPU implementation. As for the energy efficiency, the FPGA implementation was 615 times more energy efficient than GPPs, and 31 times more than GPUs. Over and above, the FPGA implementation outperformed the GPP and GPU implementations in terms of speed-up as the dimensionality of the Microarray data increases. Additionally, the DPR implementations of the K-means clustering have shown speed-up in partial reconfiguration time of ~5x and 17x over full chip reconfiguration for single-core and eight-core implementations, respectively. Two architectures of the K-NN classifier have been implemented on FPGA, namely, A1 and A2. The K-NN implementation based on A1 architecture achieved a speed-up of ~76x over an equivalent GPP implementation whereas the A2 architecture achieved ~68x speedup. Furthermore, the FPGA implementation outperformed the equivalent GPP implementation when the dimensionality of data was increased. In addition, The DPR implementations of the K-NN classifier have achieved speed-ups in reconfiguration time between ~4x to 10x over full chip reconfiguration when reconfiguring portion of the classifier or the complete classifier. Similar to K-NN, two architectures of the SVM classifier were implemented on FPGA whereby the former outperformed an equivalent GPP implementation by ~61x and the latter by ~49x. As for the DPR implementation of the SVM classifier, it has shown a speed-up of ~8x in reconfiguration time when reconfiguring the complete core or when exchanging it with a K-NN core forming a multi-classifier. The aforementioned implementations clearly show FPGAs to be an efficacious, efficient and economic solution for bioinformatics Microarrays data analysis.
119

ADH, Aspect Described Hardware-Description-Language

Park, Su-Hyun January 2006 (has links)
Currently, many machine vision, signal and image processing problems are solved on personal computers due to the low cost involved in these computers and the many excellent software tools that exist, such as MATLAB. However, computationally expensive tasks require the use of multi-processor computers that are expensive and difficult to use efficiently due to communications between the processors. In these cases, FPGAs (Field Programmable Gate Arrays) are the best choice but they are not as widely used because of lack of experience in using these devices, difficulties with algorithmic translation and immaturity of the design and implementation tools for FPGAs. Programming languages are always evolving and the programming languages for microprocessors have evolved significantly, from functional and procedural languages to object-oriented languages. Nowadays, a new paradigm called aspect-oriented software development (AOSD) is becoming more widespread. However, hardware programming languages have not evolved to the same extent as the software programming languages for microprocessors. They are still dominated by the technologies developed in 1980s, which have significant deficiencies described in this thesis. Recent advances in HDLs (Hardware Description Languages) have taken a conservative approach based on well-proven software techniques.
120

An FPGA Coprocessor for Real-Time Bathymetric Synthetic Aperture Sonar

Mulligan, David John January 2007 (has links)
The following is a thesis for a Master's degree in Electrical Engineering. It presents the design of an FPGA coprocessor for real-time bathymetric synthetic aperture sonar. Bathymetry is the process of finding the height of the seafloor; a problem that requires the computation of a large number of short-length correlations and runs slowly on a conventional microprocessor architecture. It is desirable to generate the seafloor bathymetry in real time for use as a visual aid during data gathering, thus the development of a customised coprocessor is required. The design presented utilises the system-on-chip (SoC) approach to FPGA programming, with a microprocessor, memory, communication cores and custom hardware all contained within a single chip. The merits of SoC design are examined and the details of this implementation are presented. The coprocessor communicates with a host computer over a USB link, receiving raw data as it is collected and sending processed data back to be displayed on-screen. The system was successful as a proof-of-concept, capable of processing an eighth of the area imaged by the sonar in real-time. The results for a simulated scene are presented and the performance of the current system examined with a view to improving its capabilities. While further work is required to implement a complete solution to the problem, the work carried out thus far has provided a solid base for future research.

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