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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 …
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 …
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 …
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 …
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 …
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 …
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 …
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 …
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 …
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 …
16-Bit Digital Adder Design In 250nm And 64-Bit Digital Comparator Design In 90nm Cmos Technologies, Naga Venkata Vijaya Krishna Boppana
16-Bit Digital Adder Design In 250nm And 64-Bit Digital Comparator Design In 90nm Cmos Technologies, Naga Venkata Vijaya Krishna Boppana
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High speed, low power, and area efficient adders and comparators continue to play a key role in hardware implementation of digital signal processing applications. Adders based on Complimentary Pass Transistor Logic (CPL) are power and area efficient, but are slower compared to Square Root Carry Select (SQRT-CS) based adders. This thesis demonstrates a unique custom designed 16-bit adder in 250-nm CMOS technology to obtain fast and power/area efficient features by combining CPL and CS logic. Comparing the results obtained for proposed 16-bit Linear CPL/CS adder with the BEC (Binary Excess-1 Code) based low power SQRT-CS adder, the delay is reduced …
6 Ghz Rf Cmos Active Inductor Band Pass Filter Design And Process Variation Detection, Shuo Li
6 Ghz Rf Cmos Active Inductor Band Pass Filter Design And Process Variation Detection, Shuo Li
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A 90nm CMOS active inductor band pass filter with automatic peak detection is demonstrated in this thesis. The active inductor band pass filter has a better performance than the passive band pass filter in on-chip circuit design, due to small area, larger gain and tunable frequency. However, process variation makes the active inductor band pass filter hard to be used widely in many applications. To settle this issue, an automatic voltage peak detector is introduced to detect the process variation direction and hope to be used to control the active inductor band pass filter center frequency and gain. The designed …
Multi-Finger Mosfet Low Noise Amplifier Performance Analysis, Xiaomeng Zhang
Multi-Finger Mosfet Low Noise Amplifier Performance Analysis, Xiaomeng Zhang
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Multi-finger layout technique has been extensively used in Nano-scale CMOS circuit design due to the increased circuit performance compared to a single finger layout. However choosing a finger width (W_f) and number of fingers (N_f) to optimize circuit performance is a challenging problem. In this thesis, the performances of 2.4GHz and 6.0GHz single ended low noise amplifiers (LNA) with fixed total transistor widths in 90nm CMOS technology are analyzed as function of number of fingers, bias voltage (V_bias) and channel length (L). The results show that the drain to source current, transconductance and effective gate capacitance increase with increasing number …
Impact Of Sar Image Formation Quality On Target Separability, Cody A. Lawyer
Impact Of Sar Image Formation Quality On Target Separability, Cody A. Lawyer
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The polar format algorithm (PFA) allows the use of computationally efficient fast Fourier transforms in synthetic aperture radar (SAR) image formation, but introduces phase errors when making the far-field approximations that facilitate this approach. The phase errors cause spatially variant distortion and defocus in the formed image. These effects may complicate target recognition applications. To limit the impact of defocus, scene size is usually limited such that the maximum quadratic phase error within an image falls below some threshold. This thesis looks at how distortion and defocus affects the classification of targets, with the hope of developing an application-driven scene …
Adaptive I/Q Mismatch Compensation For Wideband Receiver, Linda Zhu
Adaptive I/Q Mismatch Compensation For Wideband Receiver, Linda Zhu
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Wide working bandwidth is one of the main concerns in digital wideband receiver. The traditional digital receiver covers only one Nyquist zone, which bandwidth range is from DC to half of the sampling frequency. By utilizing in-phase/quadrature (I/Q) channels, wideband receiver is able to double the working bandwidth, which covers from DC to half of the sampling frequency and also from negative half of the sampling frequency to DC. However, I/Q mismatch in reality introduces unwanted signals, which significantly reduce the system performance and the quality of the received signals. In this thesis, an adaptive I/Q mismatch compensation technique is …