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NALLATECH IN-SOCKET FPGA FRONT-SIDE BUS ACCELERATOR

COMPUTING IN SCIENCE & ENGINEERING 2010年第2期12卷 78-82页

作者： Steffen, Craig Genest, Gildas Univ Illinois US Natl Ctr Supercomp Applicat Urbana IL 61801 USA Nallatech Cumbernauld Scotland

field-programmable gate arrays, which are more flexible than application-specific integrated circuits, have emerged as a low-power alternative to CPUs.

关键词： FPGA front-side bus accelerator field-programmable gate arrays Xeon Xilinx accelerators bandwidth compiler field programmable gate arrays field-programmable gate array low-power electronics reconfigurable socket- based accelerator

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Real-Time Digital Compensation of Current Transformers Over a Wide Frequency Range

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IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT 2010年第5期59卷 1119-1126页

作者： Gallo, Daniele Landi, Carmine Luiso, Mario Univ Naples 2 Dept Informat Engn I-81031 Aversa Italy

The advance in power electronics causes, over the years, an increasing diffusion of nonlinear loads. Moreover, electrical generation systems are going to include a growing amount of solar and wind energy, characterized by time-variant flow of energy and, very often, with a relevant distortion. These aspects give more and more emphasis to the monitoring of conducted disturbances on power systems over a wide frequency range, and consequently, voltage and current transducers adopted for this aim must have a proper frequency bandwidth. Voltage transformers (VTs) and current transformers (CTs), which are the most installed transducers in electrical power systems, are typically constructed to operate only at the industrial frequency, i.e., 50/60 Hz, but it is clear that their substitution would require an unsustainable cost. Therefore, in this paper, a method for real-time digital compensation of the CT frequency response over a wide range is presented. An implementation of the proposed method is shown, and the compensated CT is characterized and tested in some practical situations, with waveforms affected by typical power quality disturbances.

关键词： Compensation current transformer (CT) digital filter field-programmable gate array frequency response power quality

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A simple and improved digital timing method for positron emission tomography

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NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 2010年第1期622卷 219-224页

作者： Hu, Wei Choi, Yong Hong, Key Jo Kang, Jihoon Jung, Jin Ho Huh, Youn Suk Lim, Hyun Keong Kim, Sang Su Min, Byung Jun Kim, Byung-Tae Sogang Univ Dept Elect Engn Seoul 121742 South Korea Sungkyunkwan Univ Samsung Med Ctr Dept Nucl Med Sch Med Seoul 135710 South Korea

A simple and improved digital timing method was developed for positron emission tomography (PET). This method, the so-called 'initial rise interpolation method', is based on an important characteristic of gamma signals: a properly pre-amplified and sampled gamma signal pulse can be characterized to arrive with an initial rise from the baseline and then reach a maximum rise. The pulse arrival time was obtained by calculating the intersection of the initial rise line with the baseline for each gamma signal pulse. Using an 8-channel 100 MHz free-running ADC and FPGA combined data acquisition (DAQ) card, three digital timing methods were employed to measure the coincidence timing resolution of two types of recently developed 3 mm x 3 mm PET sensors (a fast and a slow CARD). The results showed that the initial rise interpolation method provides the best timing resolution for both types of GAPDs: 0.7 ns FWHM for fast GAPD and 1.5 ns FWHM for slow GAPD (digital CFD: 1.5 and 2.2 ns FWHM;maximum rise interpolation: 1.8 and 2.7 ns FWHM). By implementing the initial rise interpolation method into the FPGA of DAQ card, PET images of two F-18 line sources were acquired successfully using a pair of 4x4 GAPD-LYSO array detectors (single pixel size: 3 mm x 3 mm). The acquired image spatial resolution was a 3.1 mm FWHM. Furthermore, the simulation was performed to evaluate the effects of the pulse rise time, pulse amplitude and front-end noise level on the timing resolution estimated using the three digital timing methods. In accordance with the measurement results, the simulation results also showed that the initial rise interpolation method provided the best timing resolution. These results show that this simple and improved digital timing method is reliable and useful for the development of high performance PET. (C) 2010 Elsevier B.V. All rights reserved.

关键词： Positron emission tomography Digital timing method field-programmable gate array Geiger mode avalanche photodiode (GAPD)

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FPGA-based digital voltage-current controller for a buck converter

FPGA-based digital voltage-current controller for a buck con...

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36th Annual Conference of the IEEE Industrial-Electronics-Society (IECON)/4th IEEE International Conference on E-Learning in Industrial Electronics/IES Industry Forum

作者： Carrejo, C. E. Vidal-Idiarte, E. Estibals, B. Alonso, C. CNRS LAAS 7 Ave Colonel Roche F-31077 Toulouse France Univ Toulouse LAAS UPS INSAINPISAE F-31077 Toulouse France Univ Rovira I Virgili Tarragona Spain

ISBN: (纸本)9781424452262

This paper introduces an analysis and design of a digital controlled double loop voltage-current for a buck converter. Taking into account the implementation requirements, the chosen platform was an field-programmable gate array (FPGA). This paper also shows in detail the analog-digital interface. The study is completed by a detailed analysis of the FPGA programming including states machines and logic diagrams. Finally, theoretical results are validated with extensive simulations.

关键词： FPGA buck converter digital voltage-current controller double loop voltage-current electric current control field programmable gate arrays field-programmable gate array power convertors voltage regulators

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HARDWARE IMPLEMENTATION OF THE DISCRETE FOURIER TRANSFORM WITH NON-POWER-OF-TWO PROBLEM SIZE

HARDWARE IMPLEMENTATION OF THE DISCRETE FOURIER TRANSFORM WI...

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2010 IEEE International Conference on Acoustics, Speech, and Signal Processing

作者： Milder, Peter A. Franchetti, Franz Hoe, James C. Pueschel, Markus Carnegie Mellon Univ Dept Elect & Comp Engn Pittsburgh PA 15213 USA

ISBN: (纸本)9781424442966

In this paper, we examine several algorithms suitable for the hardware implementation of the discrete Fourier transform (DFT) with non-power-of two problem size. We incorporate these algorithms into Spiral, a tool capable of automatically generating corresponding hardware implementations. We discuss how each algorithm can be used to generate different types of hardware structures, and we demonstrate that our tool is able to produce hardware implementations of non-power-of-two sized DFTs over a wide range of cost/performance tradeoff points.

关键词： Discrete Fourier transform high-level synthesis field-programmable gate array FPGA algorithms

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HARDWARE IMPLEMENTATION OF THE DISCRETE FOURIER TRANSFORM WITH NON-POWER-OF-TWO PROBLEM SIZE

HARDWARE IMPLEMENTATION OF THE DISCRETE FOURIER TRANSFORM WI...

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IEEE International Conference on Acoustics, Speech, and Signal Processing

作者： Peter A. Milder Franz Franchetti James C. Hoe Markus Puschel Carnegie Mellon University Department of Electrical and Computer Engineering Pittsburgh PA United States

ISBN: (纸本)9781424442959

关键词： Discrete Fourier transform high-level synthesis field-programmable gate array FPGA algorithms

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Compact Rayleigh and Rician fading simulator based on random walk processes

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IET COMMUNICATIONS 2009年第8期3卷 1333-1342页

作者： Alimohammad, A. Fard, S. F. Cockburn, B. F. Schlegel, C. Univ Alberta Dept Elect & Comp Engn Edmonton AB T6G 2V4 Canada

This article describes a significantly improved sum-of-sinusoids-based model for the accurate simulation of time-correlated Rayleigh and Rician fading channels. The proposed model utilises random walk processes instead of random variables for some of the sinusoid parameters to more accurately reproduce the behaviour of wireless radio propagation. Every fading block generated using our model has accurate statistical properties on its own and hence, unlike previously proposed models, there is no need for time-consuming ensemble-averaging over multiple blocks. Using numerical simulation it is shown that the important statistical properties of the generated fading samples have excellent agreement with the theoretical reference functions. A fixed-point hardware implementation of the corresponding Rayleigh and Rician fading channel simulator on a field-programmable gate array (FPGA) is presented. By efficiently scheduling the operations, the reconfigurable fading channel simulator is compact enough that it can be efficiently used to simulate multipath scenarios and multiple-antenna systems (e. g. a 4 x 4 MIMO channel) using a single FPGA.

关键词： statistical analysis Rician fading channel simulator time-correlated compact Rayleigh channel multipath channels Logic circuits multipath scenario radiowave propagation sinusoid parameter Radiowave propagation field programmable gate arrays field-programmable gate array Rician channels antenna arrays Antenna arrays scheduling random processes statistical property simulation wireless radio propagation multiple antenna system random walk process Radio links and equipment Rayleigh channels Other topics in statistics

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A Simple and Improved Digital Timing Method for Positron Emission Tomography

A Simple and Improved Digital Timing Method for Positron Emi...

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IEEE Nuclear Science Symposium Conference 2009

作者： Hu, W. Choi, Y. Jung, J. H. Kang, J. H. Min, B. J. Huh, Y. S. Shin, S. H. Lim, H. K. Chung, Y. H. Sungkyunkwan Univ Sch Med Samsung Med Ctr Dept Nucl Med Seoul 135710 South Korea Sungkyunkwan Univ Dept Nucl Med Samsung Med Ctr Sch Med Seoul 135710 South Korea

ISBN: (纸本)9781424439614

A simple and improved digital timing method has been developed for positron emission tomography (PET). The so-called initial rise interpolation method is based on an important characteristic of gamma signal: a properly pre-amplified and sampled gamma signal pulse can be characterized to arrive with an initial rise from baseline and then to go up with a maximum rise. Pulse arrival time is obtained by calculating the intersection of the initial rise line with the baseline for each gamma signal pulse. In this study, a FPGA-based data acquisition (DAQ) card was used for data acquisition and processing. We measured coincidence timing resolution of two types (fast and slow) of recently developed 3 mm x 3 mm Geiger mode avalanche photodiodes (GAPDs) using 3 different digital timing methods: initial rise interpolation (IRO, digital CFD and maximum rise interpolation (MRI). Furthermore, simulation has been performed to evaluate effects of pulse rise time, pulse amplitude and front-end noise level on timing resolution estimated by the three digital timing methods. Measured results show that, IRI method provided the best timing resolution for both types of GAPDs: 0.7 ns FWHM for fast GAPD and 1.5 ns for slow GAPD (digital CFD: 1.5 ns and 2.2 ns;MRI: 1.8 ns and 2.7 ns). In accordance with measured results, simulation results also show that IRI method provided the best timing resolution. Based on these experimental results, we concluded that the developed simple and improved digital timing method is reliable and useful for the development of high performance PET.

关键词： Positron emission tomography Digital timing method field-programmable gate array Geiger mode avalanche photodiode (GAPD)

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Hardware acceleration of a Monte Carlo simulation for photodynamic therapy treatment planning

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JOURNAL OF BIOMEDICAL OPTICS 2009年第1期14卷 14019-1-14019-11页

作者： Lo, William Chun Yip Redmond, Keith Luu, Jason Chow, Paul Rose, Jonathan Lilge, Lothar Univ Toronto Princess Margaret Hosp Ontario Canc Inst Dept Med Biophys Toronto ON M5G 2M9 Canada Univ Toronto Edward S Rogers Sr Dept Elect & Comp Engn Toronto ON M5S 3G4 Canada

Monte Carlo (MC) simulations are being used extensively in the field of medical biophysics, particularly for modeling light propagation in tissues. The high computation time for MC limits its use to solving only the forward solutions for a given source geometry, emission profile, and optical interaction coefficients of the tissue. However, applications such as photodynamic therapy treatment planning or image reconstruction in diffuse optical tomography require solving the inverse problem given a desired dose distribution or absorber distribution, respectively. A faster means for performing MC simulations would enable the use of MC-based models for accomplishing such tasks. To explore this possibility, a digital hardware implementation of a MC simulation based on the Monte Carlo for Multi-Layered media (MCML) software was implemented on a development platform with multiple field-programmable gate arrays (FPGAs). The hardware performed the MC simulation on average 80 times faster and was 45 times more energy efficient than the MCML software executed on a 3-GHz Intel Xeon processor. The resulting isofluence lines closely matched those produced by MCML in software, diverging by only less than 0.1 mm for fluence levels as low as 0.00001 cm(-2) in a skin model. (c) 2009 Society of Photo-Optical Instrumentation Engineers. [DOI: 10.1117/1.3080134]

关键词： Monte Carlo simulation Monte Carlo multilayered media photodynamic therapy treatment planning hardware acceleration pipelining field-programmable gate array

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Design and implementation of an optical Gaussian noise generator

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OPTICAL ENGINEERING 2009年第8期48卷 085002-085002页

作者： Zao, Leonardo Loss, Gustavo Coelho, Rosangela Inst Militar Engn Dept Elect Engn Lab Res Commun & Opt Syst BR-22290 Rio De Janeiro Brazil

A design of a fast and accurate optical Gaussian noise generator is proposed and demonstrated. The noise sample generation is based on the Box-Muller algorithm. The functions implementation was performed on a high-speed Altera Stratix EP1S25 field-programmable gate array (FPGA) development kit. It enabled the generation of 150 million 16-bit noise samples per second. The Gaussian noise generator required only 7.4% of the FPGA logic elements, 1.2% of the RAM memory, 0.04% of the ROM memory, and a laser source. The optical pulses were generated by a laser source externally modulated by the data bit samples using the frequency-shift keying technique. The accuracy of the noise samples was evaluated for different sequences size and confidence intervals. The noise sample pattern was validated by the Bhattacharyya distance (Bd) and the autocorrelation function. The results showed that the proposed design of the optical Gaussian noise generator is very promising to evaluate the performance of optical communications channels with very low bit-error-rate values. (C) 2009 Society of Photo-Optical Instrumentation Engineers. [DOI: 10.1117/1.3204156]

关键词： Gaussian noise optical noise generation field-programmable gate array FSK Bhattacharyya distance

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