Electrical and Electronics Commons^™

Study Of Radiation Effects In Gan-Based Devices, Han Gao

Electrical Engineering Theses and Dissertations

Radiation tolerance of wide-bandgap Gallium Nitride (GaN) high-electron-mobility transistors (HEMT) has been studied, including X-ray-induced TID effects, heavy-ion-induced single event effects, and neutron-induced single event effects. Threshold voltage shift is observed in X-ray irradiation experiments, which recovers over time, indicating no permanent damage formed inside the device. Heavy-ion radiation effects in GaN HEMTs have been studied as a function of bias voltage, ion LET, radiation flux, and total fluence. A statistically significant amount of heavy-ion-induced gate dielectric degradation was observed, which consisted of hard breakdown and soft breakdown. Specific critical injection level experiments were designed and carried out to explore …

An Efficient Integrated Circuit Simulator And Time Domain Adjoint Sensitivity Analysis, Jiahua Li

Electrical Engineering Theses and Dissertations

In this paper, we revisit time-domain adjoint sensitivity with a circuit theoretic approach and an efficient solution is clearly stated in terms of device level. Key is the linearization of the energy storage elements (e.g., capacitance and inductance) and nonlinear memoryless elements (e.g., MOS, BJT DC characteristics) at each time step. Due to the finite precision of computation, numerical errors that accumulate across timesteps can arise in nonlinear elements.

Study Of Stochastic Market Clearing Problems In Power Systems With High Renewable Integration, Saumya Sakitha Sashrika Ariyarathne

Operations Research and Engineering Management Theses and Dissertations

Integrating large-scale renewable energy resources into the power grid poses several operational and economic problems due to their inherently stochastic nature. The lack of predictability of renewable outputs deteriorates the power grid’s reliability. The power system operators have recognized this need to account for uncertainty in making operational decisions and forming electricity pricing. In this regard, this dissertation studies three aspects that aid large-scale renewable integration into power systems. 1. We develop a nonparametric change point-based statistical model to generate scenarios that accurately capture the renewable generation stochastic processes; 2. We design new pricing mechanisms derived from alternative stochastic programming …

Second-Order Enhanced Coupling Strength Grating Out-Couplers For A Monolithic Laser-Electro-Absorption Modulator, Maryam Dezfuli

Electrical Engineering Theses and Dissertations

Conventional grating out-couplers in III-V waveguides typically require lengths of several hundreds of microns to outcouple 50 to 90% of the incident optical power. Enhanced coupling strength (ECS) gratings, which reduce the out-coupler grating length to tens of microns, have a large relative permittivity difference between the materials on either side of the grating boundary along with a high index cover layer. With appropriately chosen permittivity and layer thicknesses, the addition of a cover layer “pulls” the peak of the optical mode towards the grating region, resulting in a significant increase in the grating confinement factor. The resulting ECS out-coupler …

Enhanced Security Utilizing Side Channel Data Analysis, Michael Taylor

Computer Science and Engineering Theses and Dissertations

The physical state of a system is affected by the activities and processes in which it is tasked with carrying out. In the past there have been many instances where such physical changes have been exploited by bad actors in order to gain insight into the operational state and even the data being held on a system. This method of side channel exploitation is very often effective due to the relative difficulty of obfuscating activity on a physical level. However, in order to take advantage of side channel data streams one must have a detailed working knowledge of how a …

Three-Dimensional (3d) Memory I/O Interface Design Using Quad-Band Interconnect (Qbi) And Eight-Level Pulse Amplitude Modulation (8-Pam), Xiaoyan Wang

Electrical Engineering Theses and Dissertations

The demand for high bandwidth, low latency, reconfigurable, and small form factor memory I/O interface design has significantly increased with the development of data-intensive applications, such as artificial neural networks and high-performance computing. However, the current memory I/O interface technologies have critical limitations, such as limited bandwidth, limited pin count, long latency, non-reconfigurable data access, and large form factor. Therefore, a novel memory I/O interface design is needed to overcome these limitations.

This dissertation presents two novel memory I/O interface designs using 3D integration, QBI, and 8-PAM technologies to improve bandwidth, latency, reconfigurability, and form factor for future mobile devices. …

On-Chip Nonreciprocal Components For Full-Duplex Communications And Gaussian Regulated Gate Driver For Electromagnetic Interference Reduction, Chang Yang

Electrical Engineering Theses and Dissertations

This dissertation is comprised of two unrelated design endeavors. The first one is about two CMOS nonreciprocal components: 1) an isolator and 2) a circulator. To make the components compact enough for the next generation communication systems with wide bandwidth, both components operate at 100 GHz band for full-duplex transceivers for ultra-high-data-rate millimeter-wave wireless communication. The proposed nonreciprocal structures are based on a time-domain modulation by signals at around 1/6 of the RF frequencies and spatial duplexing over the RF signal paths, demonstrating over 45 dB isolation in a bandwidth of 1.5 GHz over the tuning range of 85-110 GHz. …

Model-Based And Data-Driven Situational Awareness For Distribution System Monitoring And Control, Ying Zhang

Electrical Engineering Theses and Dissertations

Electric power systems are undergoing a dramatic change. The penetration of distributed energy resources (DERs) such as wind turbine generators and photovoltaic panels is turning a traditional power system into the active distribution network. Power system situational awareness, which provides critical information for system monitoring and control, is being challenged by multiple sources of uncertainties such as random meter errors, stochastic power output of DERs, and imprecise network parameters. On the other hand, cyber-physical power system operation is vulnerable to cyberattacks against effective state estimation, such as false data injection attacks (FDIAs). To construct next-generation smart grids, this dissertation develops …

A 2.56 Gbps Serial Wireline Transceiver That Supports An Auxiliary Channel And A Hybrid Line Driver To Compensate Large Channel Loss, Xiaoran Wang

Electrical Engineering Theses and Dissertations

Serial transceiver links are widely used for high-speed point-to-point communications. This dissertation describes two transceiver link designs for two different applications.

In serial wireline communications, security is an increasingly important factor to concern. Securing an information processing system at the application and system software layers is regarded as a necessary but incomplete defense against the cyber security threats. In this dissertation, an asynchronous serial transceiver that is capable of transmitting and receiving an auxiliary data stream concurrently with the primary data stream is described. The transceiver instantiates the auxiliary data stream by modulating the phase of the primary data without …

Learning Deep Architectures For Power Systems Operation And Analysis, Mahdi Khodayar

Electrical Engineering Theses and Dissertations

With the rapid increase in size and computational complexities of power systems, the need for powerful computational models to capture strong patterns from energy datasets is emerged. In this thesis, we provide a comprehensive review on recent advances in deep neural architectures that lead to significant improvements in classification and regression problems in the area of power engineering. Furthermore, we introduce our novel deep learning methodologies proposed for a large variety of applications in this area. First, we present the interval deep probabilistic modeling for wind speed forecasting. Incorporating the Rough Set Theory into deep neural networks, we create an …

Application Of Optimal Switching Using Adaptive Dynamic Programming In Power Electronics, Ataollah Gogani Khiabani

Mechanical Engineering Research Theses and Dissertations

In this dissertation, optimal switching in switched systems using adaptive dynamic programming (ADP) is presented. Two applications in power electronics, namely single-phase inverter control and permanent magnet synchronous motor (PMSM) control are studied using ADP. In both applications, the objective of the control problem is to design an optimal switching controller, which is also relatively robust to parameter uncertainties and disturbances in the system. An inverter is used to convert the direct current (DC) voltage to an alternating current (AC) voltage. The control scheme of the single-phase inverter uses a single function approximator, called critic, to evaluate the optimal cost …

Reducing The Production Cost Of Semiconductor Chips Using (Parallel And Concurrent) Testing And Real-Time Monitoring, Qutaiba Khasawneh

Electrical Engineering Theses and Dissertations

Consumer electronics changed the semiconductor industry by developing many new challenges for consumer products. One of the main challenges in the consumer product is that it propelled the volume of production to massive production, e.g. hundreds of millions of cell phones are produced yearly. Combined with the overproduction of consumer products, price pressure is another challenge for consumer products. Many of the new techniques used in the design and fabrication enabled the integration of more devices in the same chips. This reduced the cost of the chips, lowered the power consumption, increased the circuit operation speed, enabled more reliable implementation, …

Parametric Amplification Study And Applications In Millimeter-Wave Transmitters, Sherry Huang

Electrical Engineering Theses and Dissertations

In wireless communication systems, the millimeter-wave frequency band has been gaining more interests recently, mainly due to its wide bandwidth and ability to support high data-rate. However, challenges come with the advantages. To transmit and receive complexed data, the quadrature amplitude modulation (QAM) scheme paired with orthogonal frequency-division multiplexing (OFDM) is used most commonly. In transmitter designs of such modulation schemes and frequency access schemes, two important requirements are high linearity and high efficiency. The building blocks of transmitters include power amplifiers (PA) and mixers. Nevertheless, traditional design techniques exhibit trade-offs between linearity and efficiency for PAs, and between conversion …

A Novel Ultrasound Imaging Technique Using Random Signals, Anahita Khalilzadeh

Electrical Engineering Theses and Dissertations

Ultrasound imaging has been used extensively because of its benign nature and relatively low cost implementation. The most common approach for forming an image is Brightness Mode (B-Mode), which uses an array with dynamic focusing. Focus is performed through Phase Shifters that are bulky and complicated components which increases the device cost.

This research describes a new method to form an Ultrasound image, without relying on phase shifting. The proposed method offers a lower cost solution compared to the B-Mode systems and overcomes some of their inherent limitations.

Using Gs/S Adc To Evaluate The Emi Of Gan-Based Power Devices, Chi Zhang

Electrical Engineering Theses and Dissertations

As the silicon-based power devices are gradually reaching their performance limits, new power transistors such as Silicon Carbide (SiC) and Gallium Nitride (GaN) FETs have been rapidly developed in recent years. GaN devices have been widely accepted by researchers for its higher speed and efficiency than silicon power devices. However, despite all its merits, the GaN device faces a more severe problem of electromagnetic interference (EMI) than the silicon device due to its high performance. Various control techniques of EMI have been studied so far and many of them require the evaluation of EMI. Research shows that the EMI level …

Investigating The Effect Of Detecting And Mitigating A Ring Oscillator-Based Hardware Trojan, Lakshmi Ramakrishnan

Electrical Engineering Theses and Dissertations

The outsourcing of the manufacturing process of integrated circuits to fabrications plants all over the world has exposed these chips to several security threats, especially at the hardware level. There have been instances of malicious circuitry, such as backdoors, being added to circuits without the knowledge of the chip designers or vendors. Such threats could be immensely powerful and dangerous against confidentiality, among other vulnerabilities.

Defense mechanisms against such attacks have been probed and defense techniques have been developed. But with the passage of time, attack techniques have improved immensely as well. From directly observing the inputs or outputs, adversaries …

Linear Phase Multi-Frequency Notch Filter Via Quadratic Programming, Yueran Ma

Electrical Engineering Theses and Dissertations

Discrete-time notch filters can be divided into infinite impulse response (IIR) and finite impulse response (FIR) notch filters. Infinite impulse response notch filters are easy to design and implement but suffer from nonlinear phase characteristics and unacceptable startup transients. Finite impulse response filters on the other hand can be designed to have linear phase but require more coefficients to achieve narrow notch widths. Multiple frequency FIR notch filters that can effectively reject several selected spectral regions while providing high transmission at frequencies outside the rejected regions have applications in communication systems, radar systems and biomedical signal processing.

A new multi-frequency …

High-Speed Single-Channel Sar Adc Using Coarse And Fine Comparators With Background Comparator Offset Calibration, Guanhua Wang

Electrical Engineering Theses and Dissertations

A 1-GS/s 8-bit single-channel successive-approximation-register (SAR) analog-to-digital converter (ADC) using coarse and fine comparators with fully background comparator offset calibration is presented. Low-power coarse comparators and low-noise fine comparators are both employed to improve the comparator power efficiency. Non-binary digital-to-analog converter (DAC) with redundancy is employed to tolerate possible errors in the most-significant-bit (MSB) decisions. A novel comparator offset calibration scheme is proposed to remove the offsets between the different comparators, without slowing down the speed of the SAR conversion. The prototype ADC is simulated in a 28 nm CMOS technology and achieves an SNDR of 42.13 dB near Nyquist …

Genetic Algorithms Vs. Simulated Annealing: A Comparison Of Approaches For Solving The Circuit Partitioning Problem, Theodore W. Manikas, James T. Cain

Computer Science and Engineering Research

An important stage in circuit design is placement, where components are assigned to physical locations on a chip. A popular contemporary approach for placement is the use of simulated annealing. While this approach has been shown to produce good placement solutions, recent work in genetic algorithms has produced promising results. The purpose of this study is to determine which approach will result in better placement solutions.

A simplified model of the placement problem, circuit partitioning, was tested on three circuits with both a genetic algorithm and a simulated annealing algorithm. When compared with simulated annealing, the genetic algorithm was found …

Surface Emitting Semiconductor Lasers And Arrays, Gary A. Evans, Jacob M. Hammer

Electrical Engineering Research

No abstract provided.