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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.
11

Micro NPU for Baseband Interconnect

Karlsson, Sara January 2014 (has links)
The aim of this work is to investigate the possibility to implement a configurable NPU (Network Processing Unit) in the next generation of Ericsson’s EMCAs (Ericsson Multi Core Architecture). The NPU is constructed so that it can be configured for either Ethernet or xIO-s, as either a transmitter or a receiver. The motive for doing the work is that many protocols have similar functions and there could be possible advantages to have a configurable protocol choice in future hardware. A model of a NPU will be created in SystemC using the TLM 2.0 interface. The model will be analyzed to evaluate its complexity regarding a possible modification to also make it configurable for CPRI. The result that is presented is that it would be possible to implement a configurable NPU in the future EMCAs. The result is based on the conclusion that the protocols use many similar functions and most of the blocks could be made configurable for use with different protocols. Configurable blocks would benefit a configurable NPU as it would require fewer resources than separate blocks for each protocol.
12

Computer Vision System-On-Chip Designs for Intelligent Vehicles

Zhou, Yuteng 24 April 2018 (has links)
Intelligent vehicle technologies are growing rapidly that can enhance road safety, improve transport efficiency, and aid driver operations through sensors and intelligence. Advanced driver assistance system (ADAS) is a common platform of intelligent vehicle technologies. Many sensors like LiDAR, radar, cameras have been deployed on intelligent vehicles. Among these sensors, optical cameras are most widely used due to their low costs and easy installation. However, most computer vision algorithms are complicated and computationally slow, making them difficult to be deployed on power constraint systems. This dissertation investigates several mainstream ADAS applications, and proposes corresponding efficient digital circuits implementations for these applications. This dissertation presents three ways of software / hardware algorithm division for three ADAS applications: lane detection, traffic sign classification, and traffic light detection. Using FPGA to offload critical parts of the algorithm, the entire computer vision system is able to run in real time while maintaining a low power consumption and a high detection rate. Catching up with the advent of deep learning in the field of computer vision, we also present two deep learning based hardware implementations on application specific integrated circuits (ASIC) to achieve even lower power consumption and higher accuracy. The real time lane detection system is implemented on Xilinx Zynq platform, which has a dual core ARM processor and FPGA fabric. The Xilinx Zynq platform integrates the software programmability of an ARM processor with the hardware programmability of an FPGA. For the lane detection task, the FPGA handles the majority of the task: region-of-interest extraction, edge detection, image binarization, and hough transform. After then, the ARM processor takes in hough transform results and highlights lanes using the hough peaks algorithm. The entire system is able to process 1080P video stream at a constant speed of 69.4 frames per second, realizing real time capability. An efficient system-on-chip (SOC) design which classifies up to 48 traffic signs in real time is presented in this dissertation. The traditional histogram of oriented gradients (HoG) and support vector machine (SVM) are proven to be very effective on traffic sign classification with an average accuracy rate of 93.77%. For traffic sign classification, the biggest challenge comes from the low execution efficiency of the HoG on embedded processors. By dividing the HoG algorithm into three fully pipelined stages, as well as leveraging extra on-chip memory to store intermediate results, we successfully achieved a throughput of 115.7 frames per second at 1080P resolution. The proposed generic HoG hardware implementation could also be used as an individual IP core by other computer vision systems. A real time traffic signal detection system is implemented to present an efficient hardware implementation of the traditional grass-fire blob detection. The traditional grass-fire blob detection method iterates the input image multiple times to calculate connected blobs. In digital circuits, five extra on-chip block memories are utilized to save intermediate results. By using additional memories, all connected blob information could be obtained through one-pass image traverse. The proposed hardware friendly blob detection can run at 72.4 frames per second with 1080P video input. Applying HoG + SVM as feature extractor and classifier, 92.11% recall rate and 99.29% precision rate are obtained on red lights, and 94.44% recall rate and 98.27% precision rate on green lights. Nowadays, convolutional neural network (CNN) is revolutionizing computer vision due to learnable layer by layer feature extraction. However, when coming into inference, CNNs are usually slow to train and slow to execute. In this dissertation, we studied the implementation of principal component analysis based network (PCANet), which strikes a balance between algorithm robustness and computational complexity. Compared to a regular CNN, the PCANet only needs one iteration training, and typically at most has a few tens convolutions on a single layer. Compared to hand-crafted features extraction methods, the PCANet algorithm well reflects the variance in the training dataset and can better adapt to difficult conditions. The PCANet algorithm achieves accuracy rates of 96.8% and 93.1% on road marking detection and traffic light detection, respectively. Implementing in Synopsys 32nm process technology, the proposed chip can classify 724,743 32-by-32 image candidates in one second, with only 0.5 watt power consumption. In this dissertation, binary neural network (BNN) is adopted as a potential detector for intelligent vehicles. The BNN constrains all activations and weights to be +1 or -1. Compared to a CNN with the same network configuration, the BNN achieves 50 times better resource usage with only 1% - 2% accuracy loss. Taking car detection and pedestrian detection as examples, the BNN achieves an average accuracy rate of over 95%. Furthermore, a BNN accelerator implemented in Synopsys 32nm process technology is presented in our work. The elastic architecture of the BNN accelerator makes it able to process any number of convolutional layers with high throughput. The BNN accelerator only consumes 0.6 watt and doesn't rely on external memory for storage.
13

Loss of acid sensing ion channel-1a and bicarbonate administration attenuate the severity of traumatic brain injury

Yin, Terry 01 May 2013 (has links)
Traumatic brain injury (TBI) is a common cause of morbidity and mortality in people of all ages. Following the acute mechanical insult, TBI evolves over the ensuing minutes and days. Understanding the secondary factors that contribute to TBI might suggest therapeutic strategies to reduce the long-term consequences of brain trauma. To assess secondary factors that contribute to TBI, we studied a lateral fluid percussion injury (FPI) model in mice. Following FPI, the brain cortex became acidic, consistent with data from humans following brain trauma. Administering HCO3- after FPI prevented the acidosis and reduced the extent of neurodegeneration. Because acidosis can activate acid sensing ion channels (ASICs), we also studied ASIC1a-/- mice and found reduced neurodegeneration after FPI. Both HCO3- administration and loss of ASIC1a also reduced functional deficits caused by FPI. These results suggest that FPI induces cerebral acidosis that activates ASIC channels and contributes to secondary injury in TBI. They also suggest a therapeutic strategy to attenuate the adverse consequences of TBI.
14

Study of Interferer Canceling Systems in a Software Defined Radio Receiver / Studie av Störsignalsneutraliserande System i en Mjukvarudefinierad Radiomottagare

Holstensson, Oskar January 2013 (has links)
This thesis describes the work related to an interferer rejection system employing frequency analysis and cancellation through phase-opposed signal injection. The first device in the frequency analysis chain, an analog fast Fourier transform application-specific integrated circuit (ASIC), was improved upon. The second device, a chained fast Fourier transform followed by a frequency analysis module employing cross-correlation for signal detection was specified, designed and implemented in VHDL.
15

SmartMedia-controller på chip / SmartMedia controller on chip

Bengtsson, Carl Johan January 2002 (has links)
This report deals with the design of a controller for SmartMedia™ flash memory cards, based on a hardware description found in the SmartMedia™ Interface Library - SMIL. The design was made on logic gate level, using standard cells in OrCAD Capture. After simulation of the design in PSpice A/D, it was exported as an EDIF netlist, which was used to make a chip layout in L-Edit, a layout tool for making integrated circuits. The layout was made using a method called Standard Place and Route - SPR, where the layout tool places standard cells from a library and connects them according to the EDIF netlist. A netlist which could be simulated in PSpice was extracted from the finished chip layout to verify that the function of the design was the same as before the transition from schematic to layout. The standard cells in the library used to make the chip layout have to meet certain criteria in order for both SPR and extraction to work and this is also discussed.
16

SmartMedia-controller på chip / SmartMedia controller on chip

Bengtsson, Carl Johan January 2002 (has links)
<p>This report deals with the design of a controller for SmartMedia™ flash memory cards, based on a hardware description found in the SmartMedia™ Interface Library - SMIL. </p><p>The design was made on logic gate level, using standard cells in OrCAD Capture. After simulation of the design in PSpice A/D, it was exported as an EDIF netlist, which was used to make a chip layout in L-Edit, a layout tool for making integrated circuits. The layout was made using a method called Standard Place and Route - SPR, where the layout tool places standard cells from a library and connects them according to the EDIF netlist. </p><p>A netlist which could be simulated in PSpice was extracted from the finished chip layout to verify that the function of the design was the same as before the transition from schematic to layout. </p><p>The standard cells in the library used to make the chip layout have to meet certain criteria in order for both SPR and extraction to work and this is also discussed.</p>
17

A Multi-Parameter Functional Side Channel Analysis Method for Hardware Trojan Detection in Untrusted FPGA Bitstreams

Bell, Christopher William 01 January 2013 (has links)
Hardware Trojan Horses (HTHs or Trojans) are malicious design modifications intended to cause the design to function incorrectly. Globalization of the IC development industry has created new opportunities for rogue agents to compromise a design in such a way. Offshore foundries cannot always be trusted, and the use of trusted foundries is not always practical or economical. There is a pressing need for a method to reliably detect these Trojans, to prevent compromised designs from being put into production. This thesis proposes a multi-parameter analysis method that is capable of reliably detecting function-altering and performance-degrading Trojans in FPGA bitstreams. It is largely autonomous, able to perform functional verification and power analysis of a design with minimal user interaction. On-the-fly test vector generation and verification reduces the overhead of test creation by removing the need to pre-generate and verify test vector sets. We implemented the method on a testbed constructed from COTS components, and tested it using a red-team/blue-team approach. The system was effective at detecting performance-degrading and function-altering embedded within combinational or sequential designs. The method was submitted for consideration in the 2012 Embedded Systems Challenge, which served to independently verify our results and evaluate the method; it was awarded first place in the competition.
18

Cryptoraptor : high throughput reconfigurable cryptographic processor for symmetric key encryption and cryptographic hash functions

Sayilar, Gokhan 03 February 2015 (has links)
In cryptographic processor design, the selection of functional primitives and connection structures between these primitives are extremely crucial to maximize throughput and flexibility. Hence, detailed analysis on the specifications and requirements of existing crypto-systems plays a crucial role in cryptographic processor design. This thesis provides the most comprehensive literature review that we are aware of on the widest range of existing cryptographic algorithms, their specifications, requirements, and hardware structures. In the light of this analysis, it also describes a high performance, low power, and highly flexible cryptographic processor, Cryptoraptor, that is designed to support both today's and tomorrow's encryption standards. To the best of our knowledge, the proposed cryptographic processor supports the widest range of cryptographic algorithms compared to other solutions in the literature and is the only crypto-specific processor targeting the future standards as well. Unlike previous work, we aim for maximum throughput for all known encryption standards, and to support future standards as well. Our 1GHz design achieves a peak throughput of 128Gbps for AES-128 which is competitive with ASIC designs and has 25X and 160X higher throughput per area than CPU and GPU solutions, respectively. / text
19

Design of a low-power interface circuitry for a vestibular prosthesis system

Toreyin, Hakan 21 September 2015 (has links)
The human vestibular system is responsible for maintaining balance and orientation, and stabilizing gaze during head motion. Head motion is sensed by vestibular sensors and encoded via the firing rate of vestibular neurons. Vestibular disorders can result in dizziness, imbalance, and disequilibrium. Currently there are no therapeutic options for individuals suffering from bilateral vestibular dysfunction. A potential solution is a vestibular prosthesis (VP). This device serves to replace peripheral vestibular organs by sensing angular motion, detected by semicircular canals (SCCs), and linear head motion, detected by the otolith organs, and selectively stimulating the corresponding vestibular afferents. An ideal VP will not only mimic the patient-dependent vestibular neural dynamics, but also consume low power. In this study, three energy-efficient ways to implement the motion encoding function required in a vestibular prosthesis are presented. Both analog and digital signal processing techniques to implement the vestibular signal processing functions are investigated.
20

Low Power Design Using RNS

Classon, Viktor January 2014 (has links)
Power dissipation has become one of the major limiting factors in the design of digital ASICs. Low power dissipation will increase the mobility of the ASIC by reducing the system cost, size and weight. DSP blocks are a major source of power dissipation in modern ASICs. The residue number system (RNS) has, for a long time, been proposed as an alternative to the regular two's complement number system (TCS) in DSP applications to reduce the power dissipation. The basic concept of RNS is to first encode the input data into several smaller independent residues. The computational operations are then performed in parallel and the results are eventually decoded back to the original number system. Due to the inherent parallelism of the residue arithmetics, hardware implementation results in multiple smaller design units. Therefore an RNS design requires low leakage power cells and will result in a lower switching activity. The residue number system has been analyzed by first investigating different implementations of RNS adders and multipliers (which are the basic arithmetic functions in a DSP system) and then deriving an optimal combination of these. The optimum combinations have been used to implement an FIR filter in RNS that has been compared with a TCS FIR filter. By providing different input data and coefficients to both the RNS and TCS FIR filter an evaluation of their respective performance in terms of area, power and operating frequency have been performed. The result is promising for uniform distributed random input data with approximately 15 % reduction of average power with RNS compared to TCS. For a realistic DSP application with normally distributed input data, the power reduction is negligible for practical purposes.

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