Electrical and Computer Engineering Commons^™

Computer Modeling Of A Solar Thermal System For Space Heating, Dhananjay D. Deshpande

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Most applications of flat plate, low-temperature solar thermal panels are for water heating, such as producing domestic hot water or raising the temperature of swimming pools. This is reasonable given that the large masses of water present in these systems inherently provide built-in thermal energy storage so that a separate energy storage tank does not have to be purchased. For a space heating system, extra thermal energy storage generally has to be purchased and is a detriment to the economics of these systems. Despite the economic drawbacks of solar thermal space heating, this thesis focuses on the size of thermal …

Designing And Simulation Of Various Class-F Radio-Frequency Power Amplifier, Varun Pundhir

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In this thesis, the various kinds of Class-F radio frequency power amplifiers are discussed. The Class-F3 RFPA is the one which has been designed and analyzed. It consists of an RF choke, blocking capacitor and a loading network. The loading network consists of a tank circuit resonating at fundamental operating frequency and also a parallel resonator circuit tuned to third harmonic. For a better understanding of the operation of Class-F3 amplifier, we go back to Class-C amplifier and discuss it briefly. Here the design remains same, operating at conduction angles less than 180 degree. The design equations were used to …

Electrical Characterization And Applications Of Supercapacitors, Avinash Lanka

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Supercapacitors have become reliable energy sources in a wide variety of applications such as automobiles, portable electronics, recreational sports equipment, medical equipment, aerospace power supplies, etc. Typically, these are electrochemical capacitors with high values of capacitance (tens or hundreds of farads) and possess the characteristics of both traditional electrolytic capacitors and batteries. They are also known as Ultra-capacitors or Electrical Double Layer Capacitors. They work on the principle of electrical double layer for charge storage. Supercapacitor have a much higher energy and power stored per unit volume over conventional capacitors. They also exhibit longer shelf life and cycle life over …

Fpga Realization Of Low Register Systolic Multipliers Over Gf(2^M), Qiliang Shao

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Finite field multiplication over GF(2^m) is a critical component for elliptic curve cryptography (ECC). National Institute of Standards and Technology (NIST) has recommended five polynomials (two trinomials and three pentanomials) for ECC implementation. Although there are a lot reports available on polynomial basis multipliers, efficient implementation of a design with flexible field-size is quite rare. There is another basis to represent the field called normal basis. Normal basis multiplication over GF(2^m) is widely used in various applications such as elliptic curve cryptography (ECC). As a special class of normal basis with low complexity, Gaussian normal basis (GNB) has received considerable …

A Genetic Algorithm For Asic Floorplanning, Anvesh Kumar Perumalla

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Semiconductor integrated circuits (ICs) have become key components in almost every aspect of our daily lives. From simple home appliances to extremely sophisticated aerospace systems, we have become increasingly dependent on ICs. System-on-chip (SoC) is an IC methodology that includes multiple design technologies on a single IC chip. SoC was developed to further integrate and manage system complexity. Due to SoC and increasingly dense IC fabrication technologies, design time and thereby system time-to-market are becoming more critical drivers of the IC design cycle. In order to address issues related to design time and time-to-market, highly optimized semiconductor intellectual property (IP) …

Multi-Carrier Radar For Target Detection And Communications, John David Ellinger

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This dissertation considers the optimization of radar performance within the structure imposed by a coded Orthogonal Frequency Division Multiplexing (OFDM) format required to achieve an acceptable communication link. The dual goal of achieving both satisfactory radar and communication performance raises challenges that can be substantively addressed by combining phase coding and modulation techniques to provide the temporal and spectral structure necessary to implement simultaneous radar and communication operations. In particular, the specific techniques, as introduced within this dissertation, of using the Multi-Frequency Complementary Phase Coded (MCPC) sequences, as prescribed by Levanon and Mozeson, for simultaneous radar and wireless communication operations …

Fpga Realization Of Low Register Systolic All One-Polynomial Multipliers Over Gf (2M) And Their Applications In Trinomial Multipliers, Pingxiuqi Chen

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All-one-polynomial (AOP)-based systolic multipliers over GF (2m) are usually not con-sidered for practical implementation of cryptosystems such as elliptic curve cryptography (ECC) due to security reasons. Besides that, systolic AOP multipliers usually suer from the problem of high register-complexity, especially in field-programmable gate array (FPGA) platforms where the register resources are not that abundant. In this thesis, however, we have shown that the AOP-based systolic multipliers can easily achieve low register-complexity implementations and the proposed architectures can be employed as computation cores to derive ecient implementations of systolic Montgomery multipli-ers based on trinomials, which are recommended by the National Institute …

Growth And Characterization Of Molybdenum Disulfide Thin Films, Carl Morris Gross Iii

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Two-dimensional materials, or materials that are only one atomic layer thick, have seen much research in recent years because of their interesting electrical properties. The first of these materials, graphene, was found to have incredible electrical properties but lacked a bandgap in intrinsic films. Without a bandgap, graphene cannot create transistors that can be shut off. Molybdenum disulfide, however, is a two-dimensional semiconductor with a large bandgap. The main issue of molybdenum disulfide is that synthesized films are a much lower quality than their exfoliated counterparts. For molybdenum disulfide to be able to be used practically, a method of synthesis …

Modular Multi-Signal Tracking Pulse Descriptor Word (Pdw) Generator With Field Programmable Gate Array (Fpga) Implementation, Justin Darrell Pelan

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As signal spectra become dense, the task of tracking and identifying radars becomes increasingly cumbersome. The variety of radars in modern theaters of war compound the task due to simultaneous operation. Real-time processing of large data sets prove difficult for sequential systems, and the parallelism of Field Programmable Gate Arrays (FPGAs) becomes an attractive option. To mitigate the increasing complexity of this task, this design proposes an FPGA architecture to produce pulse descriptor words (PDW) for up to eight independent radio frequency signals that can be used in near-real-time processing. Focusing on digital hardware techniques and modular design allow for …

Probabilistic Svm For Open Set Automatic Target Recognition On High Range Resolution Radar Data, Jason Daniel Roos

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The application of Automatic Target Recognition (ATR) on High Range Resolution (HRR) radar data in a scenario that contains unknown targets is of great interest for military and civilian applications. HRR radar data provides greater resolution of a target as well as the ability to perform ATR on a moving target, which gives it an advantage over other imaging systems. With the added resolution of HRR comes the disadvantage that a change in the aspect angle or orientation results in greater changes in the collected data, making classical ATR more difficult. Closed set ATR on HRR radar data is defined …

Nonreciprocal Magnetostatic Surface Wave In Thin Ferromagnetic Film, Kumar Vishal

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Interest in the nonreciprocal property of waves inside the magnetic material starts with its current advancement in the field of passive devices. In current technology passive devices without magnetic cores are realized on a silicon chip, usually these devices are lossy and bigger in size. Passive devices constructed with magnetic core material such as isolators, circulators, phase shifters, and gyrators; gives us the chance to minimize such losses. Nonreciprocity in magnetic material is due to the anisotropic property of permeability, it is complex in nature and represent in 3×3 matrix form. We can control the wave flow inside the nonreciprocal …

Implementation Of Logic Fault Tolerance On A Dynamically Reconfigurable Fpga, Kiran Jayarama

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Relative to integrated circuit (IC) systems, on-chip fault detection entails determi- nation of whether or not a fault exists. The cause of the fault could be some faulty logic resource or some faulty interconnect (wiring) resource, but typically, fault detection only determines if a fault exists, not what exactly is faulty. Beyond pure fault detection some work has been done relative to on-chip fault analysis to fur- ther determine not only if a fault exists, but exactly what is faulty. Even less work has been done to actually tolerate faulty resources once they have been found. For this work, we …

High-Efficiency Wideband Class-F Power Amplifier With Electronically Tunable Resonant Network, Alex D. Compton

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This thesis presents a high-efficiency Class-F power amplifier (PA) operating from 30-88 MHz through the use of an electronically tunable resonant network. While conventional Class-F designs are limited to operation over less than an octave, the proposed design utilizes reconfigurable reactive elements in order to cover the entire VHF-FM frequency range. A real circuit implementation using GaN HEMT is designed and simulated, with the notable design considerations examined in detail. A minimum power added efficiency (PAE) of 71.7% is achieved across the band, at output powers = 49.2 dBm. This combination of high output power and high-efficiency operation across a …

Gallium Nitride: Analysis Of Physical Properties And Performance In High-Frequency Power Electronic Circuits, Dalvir K. Saini

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Gallium nitride (GaN) technology is being adopted in a variety of power electronic applications due to their high efficiencies even at high switching speeds. In comparison with the silicon (Si) transistors, the GaN-based devices exhibit lower on-state resistance and parasitic capacitances. The thermal performance of the GaN transistors are also better than the Si counterparts due to their higher junction temperature and lower temperature-coefficient of on-resistance. These unique properties make the gallium-nitride power transistors an appropriate selection for power electronic converters and radio-frequency power amplifiers, where size, efficiency, power density, and dynamic performance are major requirements.

Foreseeing the immense capabilities …

A Computational Study Of A Photovoltaic Compound Parabolic Concentrator, William M. Vance

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Routines have been written and added to the Wright State developed solar system simulation program called Solar_PVHFC to model incident solar radiation for a compound parabolic concentrator (CPC) that uses solar panels (photovoltaic panels) to produce electrical energy. Solar_PVHFC is a program that models a solar energy system composed of solar panels to produce electricity from the sun, hydrogen storage tanks to chemically store the energy produced by the solar panels, and fuel cells to convert between electrical and chemical energy when required. Solar_PVHFC features several adjustable parameters to model a solar panel, hydrogen storage, and fuel cell system. Now …

Direction Of Arrival Estimation Using Wideband Spectral Subspace Projection, Majid Shaik

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Many areas such as Wireless Communication, Oil Mining, Radars, Sonar, and Seismic Exploration require the direction of arrival estimation (DOA) of wideband sources. Most existing wideband DOA estimation algorithms decompose the wideband signals into several narrowband frequency bins, followed by either focusing or transforming to a reference frequency bin, before estimating the DOAs. The focusing based methods are iterative and their performance is affected by the choice of preliminary DOA estimates and the number of source DOAs to be estimated. The existing method requiring transformation to a reference frequency bin exhibits spurious peaks in the spatial spectrum and is not …

Split Ring Resonator Design For Agricultural Based Applications, Joshua David Compaleo

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Recent advances with manufactured electromagnetic materials known as metamaterials are paving the way to use microwave technology in agricultural development and harvesting. It has been proposed that split ring resonators could be placed on the surface of fruit or vegetables such that the resonant behavior may be monitored and used to estimate the ripeness level. The method is non-destructive and could enable monitoring of large quantities of produce or even be tailored to hand-held devices for consumers. However, the understanding of corresponding changes in the proposed device's resonant behaviors and ripeness levels are limited. In addition, fruit and vegetables are …

Analysis Of The Tapered Transition Waveguide, Ryan J. Shaver

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The tapered transition waveguide is used in waveguide measurement systems for characterizing biaxial electromagnetic properties of materials, but its complex geometry does not support an analytic field solution. To ensure single-mode field behavior, the system includes sections of standard waveguides that only support the dominant mode. As a result, full-wave modeling and simulation of the system is exceedingly large.

Using the finite-element method to analyze the high-order modes at the junctions and to explore field configurations within the transition altering geometry, it is shown that besides the TE10 mode, the TE11 mode is significant. Then, two methods are proposed for …

Strain-Induced Energy Band-Gap Opening Of Silicene, Zhonghang Ji

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Inspired by the success of graphene, various two dimensional (2D) structures on different substrates have been proposed. Among others, an allotropic form of silicon, coined "silicene" was shown to exhibit similar properties with graphene of a zero band gap and a Dirac cone shape at the K point in the Brillouin zone. Similar to its counterpart graphene, one of the main obstacles to applying silicene in modern electronics is the lack of an energy band gap. In this work, a systematic study was presented on the structural and electronic properties of single and bi-layered silicon films under various in-plane biaxial …

Design And Performance Analysis Of Magnetic Adder And 16-Bit Mram Using Magnetic Tunnel Junction Transistor, Surya Kiran Akkaladevi

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The scaling down of IC's based on CMOS technology faces significant challenges due to technology advancing factors. The stand-by power becomes comparable to active power due to the increasing leakage current. Power gating and various low-power schemes have been proposed in the past to reduce the stand-by power in CMOS designs. As most random access memory (RAM) used for primary storage in personal computers is volatile memory, which needs constant voltage (power on) to store the data and results in a higher stand-by power. Magnetic Tunnel Junctions (MTJ) transistor has feature of non-volatility, endurance and high density, which makes it …

Signal Subspace Processing In The Beam Space Of A True Time Delay Beamformer Bank, Nathan Allen Wilkins

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A number of techniques for Radio Frequency (RF) source location for wide bandwidth signals have been described that utilize coherent signal subspace processing, but often suffer from limitations such as the requirement for preliminary source location estimation, the need to apply the technique iteratively, computational expense or others. This dissertation examines a method that performs subspace processing of the data from a bank of true time delay beamformers. The spatial diversity of the beamformer bank alleviates the need for a preliminary estimate while simultaneously reducing the dimensionality of subsequent signal subspace processing resulting in computational efficiency. The pointing direction of …

Hardware Trojan Detection In Cryptography Ip Cores By Library Encoding Method, Dinesh Varma Penumetcha

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Security is the primary issue in current internet world through both software and hardware. The ever increase in demand of consumer electronics requires less design cycle. To speedup design cycle, companies are approaching third parties for common applications IPs like USB, cryptography, DSP etc. These third parties can introduce a malicious content, which is called Trojan. Trojan in the netlist can activate only with special input/trigger. Available Trojan detection techniques like delay, area, power fingerprinting techniques and Automatic Test Pattern Generator (ATPG) method are not suitable as they take more time, less accurate. This thesis presents a hardware Trojan detection …

Design Of A 10-Bit 1.2 Gs/S Digital-To-Analog Converter In 90 Nm Cmos, Tyler J. Moody

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Digital analog converters bridge the gap between digital signal processing chips, and power amplifiers that transmit analog signals. Communications systems require ever increasing bandwidth, however data converters are typically the bottleneck in these systems. This thesis presents the design of a high speed current steering DAC using CMOS 90 nm technology. The resolution of the converter is 10 bits, segmented into 6 thermometer encoded MSB current cells, and 4 binary weighted LSB current cells. Each of the sub-components, such as the binary-thermometer encoder, digital latch, current cell, reconstruction filter, are discussed in detail. The current cells were designed with transistor …

Wideband Automatic Gain Control Design In 130 Nm Cmos Process For Wireless Receiver Applications, Joseph Benito Strzelecki

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An analog automatic gain control circuit (AGC) and mixer were implemented in 130 nm CMOS technology. The proposed AGC was intended for implementation into a wireless receiver chain. Design specifications required a 60 dB tuning range on the output of the AGC, a settling time within several microseconds, and minimum circuit complexity to reduce area usage and power consumption.

Desired AGC functionality was achieved through the use of four nonlinear variable gain amplifiers (VGAs) and a single LC filter in the forward path of the circuit and a control loop containing an RMS power detector, a multistage comparator, and a …

Compressive Sensing Analog Front End Design In 180 Nm Cmos Technology, Julin Mukeshkumar Shah

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In order to accurately reconstruct signal waveform a signal must be sampled at least twice as fast as the bandwidth of the signal. Ultra Wideband (UWB) signals have extraordinary potential for high information transmission while a central focus of wireless has been the mobile communication. It is an emerging area that involves development of RF sensing and spectral applications over multiple GHz bandwidths. Even though our technology is improving, it is very challenging to build ADC's that are compatible and keep up with the growth of ultra-wideband range. Compressive sensing does "sampling" and "compressing" at the same time and exploits …

Mixed Signal Detection And Parameter Estimation Based On Second-Order Cyclostationary Features, Dong Li

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Signal detection and radio frequency (RF) parameter estimation have received a lot of attention in recent years due to the need of spectrum sensing in many military and civilian communication applications. In most of existing work, the target signal is assumed to be a single RF signal with no overlapping with other RF signals. However, in a spectrally congested and spectrally contested environment, multiple signals are often mixed together at the signal detector with significant overlap in spectrum. Conventional frequency analysis through Fourier transform is not capable of detecting mixed signals with significant spectral overlap. In this thesis, we first …

Ambiguity-Based Classification Of Phase Modulated Waveforms, Anthony Buchenroth

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Accurate classification or recognition of phase modulated radar waveforms, typically accomplished via the combination of pulse parameter estimates and matched?filtering, poses a simple problem in ideal conditions. Recognition of these waveforms aids in various spectrum management, surveillance, and electronic warfare (EW) applications. In less than ideal conditions, carrier frequency, time offset, pulse amplitude, initial phase, and bandwidth are unknown to the EW receiver rendering the application of a matched filter futile. This effort investigates the use of features extracted from the ambiguity function of an intercepted pulse. Specifically, this effort will expand upon the methodology of previous work done which …

A Reconfigurable Spice-Based Cmos Lna Design In 90 Nm Technology Using Ads Rfic Dynamic Link, Pushpak Vasanth Rayudu Arja

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In this thesis, a reconfigurable dual band CMOS LNA with a switching-type circuit topology is proposed. The reconfigurable dual-band LNA can be tuned to operating fre- quency of either 1.575 GHz for global positioning system (GPS) or 2.4GHz for WLAN 802.11b standards. The simulated results performed power gain of 11.2 dB and 12.4 dB, noise figure of 3.4 dB and 2.9 dB, input return loss(S11) of -25.26 dB and-21.4 dB, third- order input intercept point of -3.12 dBm and -2.137 dBm and the design dissipates 8.9 mW and 4.68 mW of power at 1.2 V power supply at the two …

High Frequency Resolution Adaptive Thresholding Wideband Receiver System, Feiran Liu

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Fast Fourier transformation (FFT) is widely used in wideband digital receivers to detect multiple signals. To achieve high dynamic range, the receiver has to increase analog-to-digital (ADC) resolution bits, which requires significant computation time and therefore increases receiver time resolution. The other challenge of FFT approach is two signals with a small frequency difference (i.e., less than five FFT frequency bins in most cases) cannot be detected simultaneous. This thesis presents an adaptive thresholding wideband digital receiver to accurately detect two simultaneous high dynamic range signals even when they are close to one FFT frequency bin. The receiver can perform …

Wide Tuning Range I/Q Dco Vco And A High Resolution Pfd Implementation In Cmos 90 Nm Technology, Eswar Raju Suraparaju

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This thesis presents wide tuning range in-phase and quad-phase (I/Q) output digital control oscillator (DCO) and voltage control oscillator (VCO) and a simple high performance phase frequency detector (PFD) in 90 nm CMOS technology with 1.2 V power supply. The designed I/Q output DCO has an operating frequency range from 1.1-8.2 GHz with high resolution and wide linearity by using a novel skew delay structure. At 2.02GHz oscillation frequency, the measured phase noise of I/Q output DCO is -90.43dBc/Hz at an offset of 1 MHz offset and has 5 mW of power dissipation. A complementary series coupled quadrature VCO (S-QVCO) …