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Tapped-Inductor Buck Dc-Dc Converter, Ankit Chadha
Tapped-Inductor Buck Dc-Dc Converter, Ankit Chadha
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There is a high demand for low step-down dc voltage conversions. Many conventional power converters that are currently being used have a moderate conversion ratio and this may not be sufficient to meet the demand. This can be achieved by either cascading power converters or using converters with a low step-down conversion ratio. Cascading the converters increases the power conversion stage complexity and increase the order of the system, while also affecting the stability. Using converters with a high conversion ratio seems to be a more intelligent option to root. This dissertation tackles to analyze one such converter, called tapped-inductor …
High Security Cognitive Radio Network Via Instantaneous Channel Information, Kaiyu Huang
High Security Cognitive Radio Network Via Instantaneous Channel Information, Kaiyu Huang
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The cognitive radio network has been considered one of the most promising communication technologies for next generation wireless communication. One important aspect of cognitive radio network research is the so-called Primary User Authentication. Naturally, the primary user authentication in the cognitive radio network requires strong encryption. For the primary user identification, this dissertation provides a method which hides the user information in the header of the data frames with an underlay waveform. It is important to note that the underlay waveform will not bring redundancy data to the communication system. Using the synchronizing frequency as the underlay waveform carrier also …
Digital Instantaneous Frequency Measurement Receiver For Fine Frequency And High Sensitivity, Bilal Khudhur Abdulhammed Abdulhamed
Digital Instantaneous Frequency Measurement Receiver For Fine Frequency And High Sensitivity, Bilal Khudhur Abdulhammed Abdulhamed
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Wideband technology has been applied to many wide bandwidth applications when there is a need to send much different information in a short time from one point and received from another point in high precision and accuracy. A wideband receiver reports a signal without tuning if the signal is within the input bandwidth. The analog Instantaneous Frequency Measurement (IFM) receiver has been used for decades to cover a very wide input bandwidth and report one accurate frequency on a short pulse at a time. The digital IFM use a high sampling rate ADC to operate in a wide bandwidth, Hilbert …
Fault-Tolerant Mapping And Localization For Quadrotor Uav, Maximillian Andrew Gilson
Fault-Tolerant Mapping And Localization For Quadrotor Uav, Maximillian Andrew Gilson
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This research aims to accomplish three main tasks for a quadrotor UAV with mapping and navigation capabilities. Firstly, a Simultaneous Localization and Mapping (SLAM) system is developed utilizing a laser rangefinder an open source SLAM algorithm called GMapping. This system allows for mapping of the surrounding environment as well as localizing the position of the quadrotor, enabling position control. Secondly, several path planning algorithms were implemented and evaluated. This allows the quadrotor to navigate through the environment even in the presence of obstacles. Lastly, to compensate for possible faults in the SLAM measurements, a fault-tolerant control method is developed. Real-time …
Multifunctional Oxide Heterostructures For Next-Generation Tunable Rf/Microwave Electronics, Hyung Min Jeon
Multifunctional Oxide Heterostructures For Next-Generation Tunable Rf/Microwave Electronics, Hyung Min Jeon
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Recent advanced radio frequency (RF) microwave device demands for low power consumption, light weight, compact package, and high performance. To achieve the high performance, applying magnetic materials is becoming indispensable in many of those devices. Thus, the role of magnetism in those devices is important high-quality magnetic materials not only improves the performance of microwave devices but also opens opportunities in developing novel concepts of devices utilizing spin wave excitation, non-reciprocal wave propagation, and the electromagnetic coupling in multiferroic materials. Among all the others, manipulating magnetic properties in multiferroic material started a couple years ago. Multiferroic materials are a group …
Stability Analysis Of Leg Configurations For Bipedal Running, Nitin Jaiswal
Stability Analysis Of Leg Configurations For Bipedal Running, Nitin Jaiswal
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A legged robot with three-segmented limbs is used to study the effects of leg compliance originating from the joint level on the stability of hopping in place and running. The three-segments allow each leg to be kinematically configured an infinite number ways that satisfy the desired landing condition parameters, total leg length and angle. These two parameters along with the amount of energy thrust during stance determine the motion of the system during a single stride. The goal of this work is to explore the potential values for the leg parameters of three-segment leg, that provide additional stability when compared …
A Low-Area, Energy-Efficient 64-Bit Reconfigurable Carry Select Modified Tree-Based Adder For Media Signal Processing, Priscilla Sharon Allwin
A Low-Area, Energy-Efficient 64-Bit Reconfigurable Carry Select Modified Tree-Based Adder For Media Signal Processing, Priscilla Sharon Allwin
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Multimedia systems play an essential part in our daily lives and have drastically improved the quality of life over time. Multimedia devices like cellphones, radios, televisions, and computers require low-area and low-power reconfigurable adders to process greedy computation algorithms for the real-time audio/video signal and image processing such as discrete cosine transform, inverse discrete cosine transform, and fast Fourier transform, etc. In this thesis, a novel 64-bit reconfigurable adder is proposed and implemented to reduce the area and power consumption. This adder can be run-time reconfigured to different reconfigurable word lengths, i.e., one 64- bit, two 32-bits, four 16-bits or …
10-Bit C2c Dac Design In 65nm Cmos Technology, Jeevani Kommareddy
10-Bit C2c Dac Design In 65nm Cmos Technology, Jeevani Kommareddy
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Many wired and wireless communication systems require high-speed and high-performance data converters. These data converters act as bridge between digital signal processing blocks and power amplifiers. However, these data converters have been the bottleneck in the communication systems. This thesis presents the design of a 10-bit C2C digital to analog converter (DAC) for high resolution, wide bandwidth and low power consumption applications. The DAC is implemented in CMOS 65nm technology. The SFDR of this C2C DAC is 71.95dB at 500MHz input frequency and consumes 88.14µW of power with ENOB as 11.65 with 1.0GHz sample frequency with 0.31LSB of INL and …
Design Of An Ultra-Wideband Microstrip Antenna Array With Low Size, Weight And Power, Paul Staffan
Design Of An Ultra-Wideband Microstrip Antenna Array With Low Size, Weight And Power, Paul Staffan
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This study focuses on the use of microstrip antenna technology for designing an ultra-wideband antenna to meet low size, weight and power requirements. Based on the recent literature for such antennas, a quasi-log periodic microstrip antenna array is designed to operate from 8 to 40 GHz (radar bands X, Ku, K and Ka). The array consists of 33 co-linear, inset-fed, square patches on a Roger’s Duroid substrate, and is modeled using the Advanced Design System software from Keysight. The simulated results show the antenna has pass-band gains greater than 5 dB, a half-power beamwidth of 30 degrees, and linear polarization …
Two Player Zero Sum Multi-Stage Game Analysis Using Coevolutionary Algorithm, Sumedh Sopan Nagrale
Two Player Zero Sum Multi-Stage Game Analysis Using Coevolutionary Algorithm, Sumedh Sopan Nagrale
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A New Two player zero sum multistage simultaneous Game has been developed from a real-life situation of dispute between two individual. Research identifies a multistage game as a multi-objective optimization problem and solves it using Coevolutionary algorithm which converges to a solution from pareto optimal solution. A comparison is done between individual stage behaviour and multistage behaviour. Further, simulations over a range for Crossover rate, Mutation rate and Number of interaction is done to narrow down the range for a range with optimal computation speed. A relationship has been observed which identifies a relationship between population size, number of interactions, …
System Identification And Model-Based Control Of Quadcopter Uavs, Andrew P. Szabo
System Identification And Model-Based Control Of Quadcopter Uavs, Andrew P. Szabo
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As control systems become more sophisticated, more accurate system models are needed for control law design and simulation. In this research, a nonlinear dynamic model of a quadcopter UAV is presented and model parameters are estimated off-line using in-flight experimental data. In addition, a model-based classical control law for the quadcopter UAV is designed, simulated, and then deployed in UAV flight tests. The intent of this research is to identify a model which may be simple enough to easily use for control law design, and accurate enough for simulation. In addition, a model-based classical control law is designed to for …
True-Average Current-Mode Control Of Dc-Dc Power Converters: Analysis, Design, And Characterization, Dalvir K. Saini
True-Average Current-Mode Control Of Dc-Dc Power Converters: Analysis, Design, And Characterization, Dalvir K. Saini
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Energy efficient, wide-bandwidth, and well-regulated dc-dc power converters are in great demand in today's emerging technologies in areas such as medical, communication, aerospace, and automotive industries. In addition to design and selection of the converter components, a robust closed-loop modeling is very essential for reliable power-electronic systems. Two closed-loop control techniques for power converters exist: voltage-mode control and current-mode control. The principles of voltage-mode control have been explored in great depths by researchers over the last two decades. However, the dynamic modeling of current-mode controlled dc-dc power converters has many uncharted areas that needs careful attention. Two main methods exist …
Examination Of Gain Scheduling And Fuzzy Controllers With Hybrid Reachability, Aaron W. Fifarek
Examination Of Gain Scheduling And Fuzzy Controllers With Hybrid Reachability, Aaron W. Fifarek
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Modern aircraft with nonlinear flight envelopes predominately utilize gain scheduled controllers to provide stability of flight. Using gain scheduled control techniques, nonlinear envelopes can be linearized into collections of linear systems that operate under various system dynamics. Linear controllers approximate the nonlinear response over setpoints of operating conditions which allow traditional linear theory to be applied to maintain stability. Techniques to prove linear stability are well understood and realized in control systems, but when controllers are switched, interpolation methods must be used. Interpolation is necessary as gain scheduled systems do not have foundational switching paradigms as part of their realization …
Wideband Doa And Parameter Estimation Of Chirp Sources Using Dcft And Compressive Sensing, Luay A. Al Irkhis
Wideband Doa And Parameter Estimation Of Chirp Sources Using Dcft And Compressive Sensing, Luay A. Al Irkhis
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Direction of Arrival (DoA) estimation of chirp sources has many applications in radar, sonar and medical imaging. This work considers DoA and parameter estimation of wide- band chirp sources by the use of Discrete Chirp Fourier Transform (DCFT), its Compres- sive Sensing formulation (CS-DCFT) and Distributed CS. DCFT is similar to traditional Discrete Fourier Transform (DFT) but with chirp ba- sis and two-dimensional search over chirp rate and chirp frequency. For chirp parame- ters estimation, the proposed Compressive Sensing (CS) formulation uses the parametric DCFT basis to achieve superior estimator performance in polynomial time using Orthog- onal Matching Pursuit (OMP) …
Feed-Forward Compensation Of Non-Minimum Phase Systems, Venkatesh Dudiki
Feed-Forward Compensation Of Non-Minimum Phase Systems, Venkatesh Dudiki
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Due to inherent limitations posed by existence of zeros of a transfer function in the righthalfof the complex plane, known as non-minimum phase zeros, the issue of dealing withsuch zeros is extremely important in control of linear systems. Considerable literatureexists in control theory to try and minimize or eliminate the effect of non-minimum phasezeros. These include pole-zero cancellation, feedforward compensation, among others.These methods are only limited only to stable systems (systems with poles in the left halfof the complex plane); and will fail for systems that are unstable as well as non-minimumphase.This research focuses in designing feedforward compensators for unstable …
Hardware Security And Vlsi Design Optimization, Hao Xue
Hardware Security And Vlsi Design Optimization, Hao Xue
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Microelectronic circuit is ubiquitous component of modern electrical devices. The increasing complexity and professionality of phases in microelectronic supply chain bring more global cooperation to integrated circuit (IC) production. Therefore, providing a secure environment for microelectronic circuit design does not ensure the integrity of the hardware since any participator of IC fabrication has the opportunity to implant a malicious alteration in original IC design. Especially overseas chip-fabrication is a vital potential threat for national defense products. In theory, anyone who has access to fabrication process can tamper with the original design, with the potential to change function, modify parametric properties …
Thz Sources Based On Er-Doped Gaas Driven At Telecom-Fiber Wavelengths, Andrea Mingardi
Thz Sources Based On Er-Doped Gaas Driven At Telecom-Fiber Wavelengths, Andrea Mingardi
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This dissertation entails the investigation of ultrafast photoconductive (PC) THz sources driven by fiber and semiconductor lasers around λ= 1550-nm to utilize commercial fiber-optic telecom technology. The preferred approach is to use GaAs with a high concentration of erbium, which has performed well when driven with laser sources at both 800 nm wavelength, through intrinsic photoconductivity, and 1550 nm, through extrinsic photoconductivity. Studies in the early 1990s showed that the Er doping level has a solubility limit of ~ 7 × 1017 cm−3 at 580 °C, above which erbium is incorporated into GaAs as ErAs nanoparticles which promote resonant absorption …
Resonant Gate-Drive Circuits For High-Frequency Power Converters, Hur Jedi
Resonant Gate-Drive Circuits For High-Frequency Power Converters, Hur Jedi
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The development trend of power converters motivates the pursuit with high density, high efficiency, and low cost. Increasing the frequency can improve the power density and lead to small passive elements and a fast dynamic response. Each one of these power converters must be driven by a gate-drive circuit to operate efficiently. Conventional gate-drivers are used up to frequencies of about 5 MHz and suffer from switching losses. Therefore, the development of switch-mode power supplies (SMPS) operating at high frequencies requires high-speed gate drivers. The presented research in this dissertation focuses on analysis, design, and development of new types of …
Switching Neural Network Systems For Nonlinear Tracking, Manoj Ghimire
Switching Neural Network Systems For Nonlinear Tracking, Manoj Ghimire
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In this thesis, we consider the problem of tracking in complex nonlinear dynamical systems. While the Kalman filter is known to be the mean-squared error optimal tracker under linear dynamics and linear measurements, more sophisticated models and algorithms are required for complex dynamics. Here, we consider switching systems where the dynamical properties vary (''switch modes") over time. For example, the dynamics of a vehicle may switch as it transitions from interstate to urban conditions, human speech dynamics switch as speakers change, and stock market dynamics switch with discrete news events. In this work, we use mode-dependent neural networks to capture …
Chaotic Based Self-Synchronization For Rf Steganography Radar/Communication Waveform, Michael A. Gonnella
Chaotic Based Self-Synchronization For Rf Steganography Radar/Communication Waveform, Michael A. Gonnella
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In this project, we continue previous CSR project entitled RF Steganography based Joint Radar/Communication Waveform Design to develop a bio-inspired secure low probability detection (LPD) radio frequency (RF) waveform that can serve multiple purposes simultaneously. Previously, we have developed an RF steganography based RF waveform to conceal a secure digital communication within a linear frequency modulated (LFM) chirp radar signal. By exploiting novel reduced phase shift keying modulation and variable symbol duration, the new waveform is resistant to time domain analysis, frequency domain analysis and cyclostationary analysis. However, to demodulate the hidden communication message, the intended receiver has to know …
Temperature Robust Longwave Infrared Hyperspectral Change Detection, Nicholas A. Durkee
Temperature Robust Longwave Infrared Hyperspectral Change Detection, Nicholas A. Durkee
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In this thesis, we develop and evaluate change detection algorithms for longwave infrared (LWIR) hyperspectral imagery. Because measured radiance in the LWIR domain depends on unknown surface temperature, care must be taken to prevent false alarms resulting from in-scene temperature differences that appear as material changes. We consider fewer variables. Examples using synthetic and measured data quantify the computational complexity of the proposed methods and demonstrate orders of magnitude reduction in false alarm rates relative to existing methods. Four strategies to mitigate this effect. In the first, pre-processing via traditional temperatureemissivity separation yields approximately temperature-invariant emissivity vectors for use in …
Display And Analysis Of Tomographic Reconstructions Of Multiple Synthetic Aperture Ladar (Sal) Images, Bassirou Seck
Display And Analysis Of Tomographic Reconstructions Of Multiple Synthetic Aperture Ladar (Sal) Images, Bassirou Seck
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Synthetic aperture ladar (SAL) is similar to synthetic aperture radar (SAR) in that it can create range/cross-range slant plane images of the illuminated scatters; however, SAL has wavelengths 10,000x smaller than SAR enabling a relatively narrow real aperture, diffraction limited beam widths. The relatively narrow real aperture resolutions allow for multiple slant planes to be created for a single target with reasonable range/aperture combinations. These multiple slant planes can be projected into a single slant plane projections (as in SAR). It can also be displayed as a 3-D image with asymmetric resolutions, diffraction limited in the dimension orthogonal to the …
Implementation Of High Speed And Low Power Radix-4 8*8 Booth Multiplier In Cmos 32nm Technology, Rishit Navinbhai Patel
Implementation Of High Speed And Low Power Radix-4 8*8 Booth Multiplier In Cmos 32nm Technology, Rishit Navinbhai Patel
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According to Moore’s law, number of transistors integrated on a single chip double every 18 months with a lot new functionality embedded, which results the increasing of delay and power consumption of a chip. To improve the performance of a more complicated digital circuit design, faster and power efficient digital sub-components are in urgent need. Multipliers are the key components in the field of DSP, GPU and CPU which compute enormous amount of binary data. A radix-4 8*8 booth multiplier is proposed and implemented in this thesis aiming to reduce power delay product. Four stages with different architecture are used …
Analysis And Design Of High-Frequency Soft-Switching Dc-Dc Converter For Wireless Power Charging Applications, Abhishek V. Danekar
Analysis And Design Of High-Frequency Soft-Switching Dc-Dc Converter For Wireless Power Charging Applications, Abhishek V. Danekar
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Wireless power transfer (WPT) technology is becoming attractive in a wide variety of applications such as electric-vehicle charging, induction heating, charging portable applications, industrial robots, and biomedical implants. Recent studies have shown various techniques to implement wireless power transfer and these techniques differ based on the type of applications. For example, for electric vehicle charging, the power levels are in the range 5 kW to 25 kW and the operating frequency is in the range 70 kHz to 110 kHz. On the other hand, for consumer applications, the power levels vary from a few watts to hundreds of watts and …
Gnss Receiver Testing And Algorithm Development, Rachael E. Kolker
Gnss Receiver Testing And Algorithm Development, Rachael E. Kolker
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Many current GNSS Software Defined Receivers (SDRs) are often limited in what they can do across a range of developmental applications. They cannot perform acquisition and tracking without several iterations of coding, which does not allow for fast processing. This work provides a Matlab SDR that is based on freely available and optimized components that can be applied to all GNSS signals. A previous basis has been expanded upon to perform tracking of QZSS signals. In addition to this, two separate hardware front ends were compared and their differences analyzed. These hardware systems collected data with different disciplining clocks, but …
Improvement Of Continuous Wave Radar Measurements In A Partially Controlled Environment, Jared Smith
Improvement Of Continuous Wave Radar Measurements In A Partially Controlled Environment, Jared Smith
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A continuous wave (CW) radar system within a partially controlled environment measures scale model aircraft for mono-static and fully polarimetric radar imaging. Due to a pseudo-far-field setup, wavefront curvature manifests primarily as geometric distortion. Recently proposed phase error models show induced geometric distortion to be independent of aperture size which are verified via measurement for Sensors and Signals Exploitation Laboratory (SSEL) collections. The partially controlled nature of the SSEL introduces stray infrastructural reflections into the measured data. Three methods to reduce stray signals are explored namely: true background subtraction (TBS), running average (RA), and spatial filtering (SF). Of the three …
Extended Kalman Filter And Lqr Controller Design For Quadrotor Uavs, Muneeb Masood Raja
Extended Kalman Filter And Lqr Controller Design For Quadrotor Uavs, Muneeb Masood Raja
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A quadrotor is a unique class of UAVs with vertical take off and landing (VTOL) capability and has attracted significant attention due to its importance in various applications. This thesis presents the design and experimental implementation of Extended Kalman Filters (EKFs) to estimate the states of a quadrotor and a Linear Quadratic Regulator (LQR) controller with integral action to meet the desired control objectives. In case of the Extended Kalman Filters, two different situations are considered: (1) all the states including the Inertial Measurement Unit (IMU) biases are estimated; (2) only the attitude, altitude, and vertical velocity are estimated. The …
An Engage Or Retreat Differential Game With Mobile Agents, Swathi Chandrasekar
An Engage Or Retreat Differential Game With Mobile Agents, Swathi Chandrasekar
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The thesis is aimed at developing optimal defensive strategies that dissuade an attacker from engaging a defender while simultaneously persuading the attacker to retreat. A two-player Engage or Retreat differential game is developed in which one player represents a mobile attacker and the other player represents a mobile defender. Both players are modeled as massless particles moving with constant velocity. The choice to terminate the game in engagement or retreat lies with the attacker. The defender indirectly influences the choice of the attacker by manipulating the latter's utility function. In other words, the defender co-operates with the attacker so that …
Rf Cmos Band Pass Filters With Wide Tuning Frequency, Controllable Pass Band And High Stopband Rejection: Using Passive And Active Inductors, Jian Chen
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With the increasing demand for high performance RF front-end modules, like multimedia handset and base station devices accommodating multiple wireless standards (2G, 2.5G, 3G, WiMAX, and LTE). Multiple IF amplifiers, mixers, RF band pass filters (BPFs), modulators and demodulators are desired to be tunable to meet dynamic standards with different frequency bands. Tunable devices with wide tuning frequency range, tuning speed, high linearity, energy conservative, high pass band gain, high stop band rejection are the paramount components in the reconfigurable RF front-end systems. In this dissertation, first a wide tuning passive inductor band pass filter (BPF) with steep roll-off high …
Hysteretic Controlled Dc-Dc Converters, Shweta Chauhan
Hysteretic Controlled Dc-Dc Converters, Shweta Chauhan
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Switched-mode DC-DC converters are widely used in applications requiring step-up and step-down of DC voltages or currents. These converters find their use in portable applications such as laptops and smart phones, radio-frequency power amplifiers, as light emitting diode (LED) drivers, etc. The power converters consist of a switching network, energy storage elements such as inductors and capacitors, and a load resistor. Transformers are used in converters, which require isolation. The switching network comprises of MOSFETs and diodes. With improvement in the VLSI technology, smaller MOSFETs with increased power handling capability are pushing the speed of operation of these power converters …