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Ip Protection For Dsp Algorithms' Fpga Implementation., Wei Dai
Ip Protection For Dsp Algorithms' Fpga Implementation., Wei Dai
Electronic Theses and Dissertations
With today's system-on-chip (SOC) technology, we are able to design larger and more complicated application-specific integrated circuits (ASICs) and field programmable gate array (FPGA) in shorter time period. The key point of the success of SOC technology is the reuse of intellectual property (IP) cores. Consequently the copyright protection for these IP cores becomes the major concern for the development pace of SOC technology. Watermarking technology has been proved to be an effective way of copyright protection. In this thesis, the author presents two new watermarking algorithms respectively at algorithm level and FPGA layout level. The simulations and implementation results …
Adaptive Noise Cancellation Using Multichannel Lattice Structure., Qing Xie
Adaptive Noise Cancellation Using Multichannel Lattice Structure., Qing Xie
Electronic Theses and Dissertations
This thesis presents a multichannel adaptive noise cancellation technique (MCLS) for cancelling the noise over nonlinear transmission channel. The technique applies to the situation in which the reference signal and noisy primary signal are collected simultaneously. The coefficients of the multichannel multiple regression transversal filter are modified adaptively according to the backward prediction error vector generated from the multichannel adaptive lattice predictor. This multichannel adaptive noise cancellation procedure involves the NLMS adaptive algorithm. The performance of the new technique using different types of transmission channels, different types of reference inputs and different types of noise-free primary inputs are examined analytically. …
A Game Theoretic Approach To Control Of A Hybrid Electric Vehicle Powertrain., Alan. Soltis
A Game Theoretic Approach To Control Of A Hybrid Electric Vehicle Powertrain., Alan. Soltis
Electronic Theses and Dissertations
The automotive community has long dealt with concerns over the environmental impact of personal transportation methods. Such concerns, coupled with political concerns such as gasoline prices, and increasing dependence on foreign oil has increased the research effort into alternative concepts for vehicle powertrains. One of the most prominent technologies is the hybrid electric vehicle (HEV). Many HEVs employ both an internal combustion engine and an electric motor. The goal is to provide lower emissions, while obtaining superior fuel economy and performance. The objective of this thesis is to explore the use of game-theoretic principles in the implementation of supervisory control …
A Sigmadelta Modulator For Digital Hearing Instruments Using 0.18 Mum Cmos Technology., Iman Yassin. Taha
A Sigmadelta Modulator For Digital Hearing Instruments Using 0.18 Mum Cmos Technology., Iman Yassin. Taha
Electronic Theses and Dissertations
This thesis develops the design methodology for a low-voltage low-power SigmaDelta Modulator, realized using a switched op-amp technique that can be used in a hearing instrument. Switched op-amp implementation allows scaling down the design to the latest CMOS technology. A single-loop second-order SigmaDelta Modulator topology is chosen. The modulator circuit features reduced complexity, area reduction and low conversion energy. The modulator has a sampling rate of 8.2 MHz with an over-sampling ratio (OSR) of 256 to provide an audio bandwidth of 16 kHz. The modulator is implemented in a 0.18 mum digital CMOS technology with metal-to-metal sandwich structure capacitors. The …
Design Of Quadrature Mirror Filter Banks With Canonical Signed Digit Coefficients Using Genetic Algorithms., Haritha Uppalapati
Design Of Quadrature Mirror Filter Banks With Canonical Signed Digit Coefficients Using Genetic Algorithms., Haritha Uppalapati
Electronic Theses and Dissertations
This thesis is about the use of a genetic algorithm to design QMF bank with canonical signed digit coefficients. A filter bank has applications in areas like video and audio coding, data communication, etc. Filter bank design is a multiobjective optimization problem. The performance depends on the reconstruction error of the overall filter bank and the individual performance of the composing lowpass filter. In this thesis we have used reconstruction error of the overall filter bank as our main objective and passband error, stopband error, stopband and passband ripples and transition width of the individual lowpass filter as constraints. Therefore …
Computer Simulation Of Transient Stability Analysis Of Power Systems., N. S. K. Jayasekara Menike
Computer Simulation Of Transient Stability Analysis Of Power Systems., N. S. K. Jayasekara Menike
Electronic Theses and Dissertations
Determination of stability characteristics of a power system is considered as a substantial issue with the increasing complexity of power systems. Power system stability is defined as the behavior of the electrical power system under sudden or sequence of disturbances when it is operating in steady state. It could be a problem of voltage stability, frequency stability or rotor angle stability depending of the type of disturbance. Transient stability which is a sub section of rotor angle stability, is concerned with the condition in which the synchronous machines in the system remain in synchronism or 'in-step' with each other when …
New Vlsi Design Of A Map/Bcjr Decoder., Leila Sabeti
New Vlsi Design Of A Map/Bcjr Decoder., Leila Sabeti
Electronic Theses and Dissertations
Any communication channel suffers from different kinds of noises. By employing forward error correction (FEC) techniques, the reliability of the communication channel can be increased. One of the emerging FEC methods is turbo coding (iterative coding), which employs soft input soft output (SISO) decoding algorithms like maximum a posteriori (MAP) algorithm in its constituent decoders. In this thesis we introduce a design with lower complexity and less than 0.1dB performance loss compare to the best performance observed in Max-Log-MAP algorithm. A parallel and pipeline design of a MAP decoder suitable for ASIC (Application Specific Integrated Circuits) is used to increase …
Low Power Cmos Analog Multipliers., Zheng Li
Low Power Cmos Analog Multipliers., Zheng Li
Electronic Theses and Dissertations
CMOS analog multiplier is a very important building block and programming element in analog signal processing. Although high-performance multipliers using bipolar transistors have been available for 40 years, CMOS multiplier implementation is still a challenging subject especially for low-power and low-noise circuit design. Since the supply voltage is normally fixed for analog multiplier structures, we use the total current to represent the power dissipation. Our basic idea for low power design of analog multipliers is to fit most of the transistors into the linear region, while at the same time keeping the drain-to-source voltage as low as possible to decease …
Steady State Stability Enhancements Using A Parallel Small Power Dc Link., Ravindra Premathilaka Mutukutti Arachchige
Steady State Stability Enhancements Using A Parallel Small Power Dc Link., Ravindra Premathilaka Mutukutti Arachchige
Electronic Theses and Dissertations
The objective of this thesis to demonstrate the validity of a new concept in dynamic stability enhancement of a synchronous Generator connected to the grid via an AC transmission line, using a small power parallel DC link. Superior ability of rapid modulation of power in a DC transmission line is used to damp the oscillations in order to enhance the stability as well as to increase the power transfer capability. A Matlab-Simulink model was developed to compare the dynamic responses of the system with and without the proposed DC damping scheme. The simulations revealed that the use of a small …
Space-Time Coding With Imperfect Channel Estimates., Bashir Iqbal Morshed
Space-Time Coding With Imperfect Channel Estimates., Bashir Iqbal Morshed
Electronic Theses and Dissertations
This thesis proposes a new decision rule for the space-time block (STB) coded wireless communication system in Rayleigh faded channel with partial knowledge of the channel state information (CSI). Also proposed is the frame-based iterative channel estimation algorithm for the same system with no knowledge of CSI. This thesis proposes a simpler modified decision rule which performs better in terms of bit error rate than the existing state-of-the-art technique using gray coded 16-QAM scheme with 2 transmitter antennas and 1 receiver antenna. The thesis also proposes the frame-based iterative channel estimator when no knowledge of CSI is available at the …
Bit-Parallel Word-Serial Polynomial Basis Finite Field Multiplier In Gf(2(233))., Wenkai Tang
Bit-Parallel Word-Serial Polynomial Basis Finite Field Multiplier In Gf(2(233))., Wenkai Tang
Electronic Theses and Dissertations
Smart card gains extensive uses as a cryptographic hardware in security applications in daily life. The characteristics of smart card require that the cryptographic hardware inside the smart card have the trade-off between area and speed. There are two main public key cryptosystems, these are RSA cryptosystem and elliptic curve (EC) cryptosystem. EC has many advantages compared with RSA such as shorter key length and more suitable for VLSI implementation. Such advantages make EC an ideal candidate for smart card. Finite field multiplier is the key component in EC hardware. In this thesis, bit-parallel word-serial (BPWS) polynomial basis (PB) finite …
Robust Control For An Electric Power Steering System., Ke Li
Robust Control For An Electric Power Steering System., Ke Li
Electronic Theses and Dissertations
The EPS (electric power steering) system is one of the safety-critical systems in modern automotive control system. In this thesis, a dynamic model for an EPS system was derived. And then, new controller architecture with an extra logical controller in the steering feedback loop, called motion controller, was proposed to increase the sensitivity of the control system to the system. Finally, a robust control system was designed based on the proposed EPS model and the new controller architecture. The disturbance signal is the high frequency part of the torque from road to the rack and pinion. The disturbance can be …
Asynchronous Design Of A Multi-Dimensional Logarithmic Number System Processor For Digital Hearing Instruments., Jiansong Wu
Asynchronous Design Of A Multi-Dimensional Logarithmic Number System Processor For Digital Hearing Instruments., Jiansong Wu
Electronic Theses and Dissertations
This thesis presents an asynchronous Multi-Dimensional Logarithmic Number System (MDLNS) processor that exhibits very low power dissipation. The target application is for a hearing instrument DSP. The MDLNS is a newly developed number system that has the advantage of reducing hardware complexity compared to the classical Logarithmic Number System (LNS). A synchronous implementation of a 2-digit 2DLNS filterbank, using the MDLNS to construct a FIR filterbank, has successfully proved that this novel number representation can benefit this digital hearing instrument application in the requirement of small size and low power. In this thesis we demonstrate that the combination of using …
Frequency Dependent Dielectric Constants And Its Numerical Computation Through Kramers-Kronig Relations And Hilbert Transform., Ruwan D. Weerasundara
Frequency Dependent Dielectric Constants And Its Numerical Computation Through Kramers-Kronig Relations And Hilbert Transform., Ruwan D. Weerasundara
Electronic Theses and Dissertations
The dielectric constant and loss are important (real and imaginary components) properties of interest to electrical engineers because these two parameters, among others, decide the suitability of a material for a given application. The nature of some physical important parameters is such that frequency dependent real and imaginary components cannot be specified independently from each other. The Kramers-Kronig relations provide the coupling between real and imaginary components. Occasions arise when only one of the components can be readily obtained from theoretical or experimental procedures. The mathematical technique used by Kramers-Kronig relations, which allows one component to be defined in terms …
Computer Analysis Of Composite Documents With Non-Uniform Background., Yasser Alginahi
Computer Analysis Of Composite Documents With Non-Uniform Background., Yasser Alginahi
Electronic Theses and Dissertations
The motivation behind most of the applications of off-line text recognition is to convert data from conventional media into electronic media. Such applications are bank cheques, security documents and form processing. In this dissertation a document analysis system is presented to transfer gray level composite documents with complex backgrounds and poor illumination into electronic format that is suitable for efficient storage, retrieval and interpretation. The preprocessing stage for the document analysis system requires the conversion of a paper-based document to a digital bit-map representation after optical scanning followed by techniques of thresholding, skew detection, page segmentation and Optical Character Recognition …
Drive Control And Real-Time Simulation For Switched Reluctance Motor In A Fuel Cell Power System., Meranda Salem
Drive Control And Real-Time Simulation For Switched Reluctance Motor In A Fuel Cell Power System., Meranda Salem
Electronic Theses and Dissertations
Switched Reluctance Motor (SRM) drive is considered as a possible alternative to other conventional variable-speed drives because of several advantages [1], [2]. However, in order for the performance of a switched reluctance motor drive to suit several applications, it has to be tailored through appropriate control. Rotor position sensing is an integral part of SRM control because of the nature of torque production. Sensorless control reduces overall cost and dimension of the drive in addition to improving reliability. In this thesis, an Inductance Model Based Sensorless [8] Switched Reluctance Motor is used to design the drive controller for SRM. A …
A 12-Bit, 40 Msamples/S, Low-Power, Low-Area Pipeline Analog-To-Digital Converter In Cmos 0.18 Mum Technology., Mani Mohajerin
A 12-Bit, 40 Msamples/S, Low-Power, Low-Area Pipeline Analog-To-Digital Converter In Cmos 0.18 Mum Technology., Mani Mohajerin
Electronic Theses and Dissertations
With advancements in digital signal processing in recent years, the need for high-speed, high-resolution analog-to-digital converters (ADCs) which can be used in the analog front-end has been increasing. Some examples of these applications are image and video signal processing, wireless communications and asymmetrical digital subscriber line (ADSL). In CMOS integrated circuit design, it is desirable to integrate the digital circuit and the ADC in one microchip to reduce the cost of fabrication. Consequently the power dissipation and area of the ADCs are important design factors. The original contributions in this thesis are as follows. Since the performance of pipeline ADCs …