Engineering Commons^™

A Low-Power Bfsk/Ook Transmitter For Wireless Sensors, Mohammed Shahriar Jahan

Doctoral Dissertations

In recent years, significant improvements in semiconductor technology have allowed consistent development of wireless chipsets in terms of functionality and form factor. This has opened up a broad range of applications for implantable wireless sensors and telemetry devices in multiple categories, such as military, industrial, and medical uses. The nature of these applications often requires the wireless sensors to be low-weight and energy-efficient to achieve long battery life. Among the various functions of these sensors, the communication block, used to transmit the gathered data, is typically the most power-hungry block. In typical wireless sensor networks, transmission range is below 10 …

A Ghz-Range, High-Resolution Multi-Modulus Prescaler For Extreme Environment Applications, Benjamin Matthew Mccue

Doctoral Dissertations

The generation of a precise, low-noise, reliable clock source is critical to developing mixed-signal and digital electronic systems. The applications of such a clock source are greatly expanded if the clock source can be configured to output different clock frequencies. The phase-locked loop (PLL) is a well-documented architecture for realizing this configurable clock source. Principle to the configurability of a PLL is a multi-modulus divider. The resolution of this divider (or prescaler) dictates the resolution of the configurable PLL output frequency. In integrated PLL designs, such a multi-modulus prescaler is usually sourced from a GHz-range voltage-controlled oscillator. Therefore, a fully-integrated …

A Magnetic Actuated Fully Insertable Robotic Camera System For Single Incision Laparoscopic Surgery, Xiaolong Liu

Doctoral Dissertations

Minimally Invasive Surgery (MIS) is a common surgical procedure which makes tiny incisions in the patients anatomy, inserting surgical instruments and using laparoscopic cameras to guide the procedure. Compared with traditional open surgery, MIS allows surgeons to perform complex surgeries with reduced trauma to the muscles and soft tissues, less intraoperative hemorrhaging and postoperative pain, and faster recovery time. Surgeons rely heavily on laparoscopic cameras for hand-eye coordination and control during a procedure. However, the use of a standard laparoscopic camera, achieved by pushing long sticks into a dedicated small opening, involves multiple incisions for the surgical instruments. Recently, single …

Isolated Wired And Wireless Battery Charger With Integrated Boost Converter For Phev And Ev Applications, Madhu Sudhan Chinthavali

Doctoral Dissertations

Vehicle charging and vehicle traction drive components can be integrated for multi-functional operations, as these functions are currently operating independently. While the vehicle is parked, the hardware that is available from the traction drive can be used for charging. The only exception to this would be the dynamic vehicle-charging concept on roadways. WPT can be viewed as a revolutionary step in PEV charging because it fits the paradigm of vehicle to infrastructure (V2I) wirelessly. WPT charging is convenient and flexible not only because it has no cables and connectors that are necessary, but due more to the fact that charging …

Uwb Precise Indoor Localization System Performance, Limitations And Its Integration, Essam Abdelkadir Elkhouly

Doctoral Dissertations

An indoor localization system that was built at University of Tennessee is extensively studied and improved. The goal of the system is to achieve mm down to sub-mm accuracy/precision.

Sub-sampling is used to alleviate the high sampling rate required for UWB signals. Current commercial direct sampling systems are still too slow or prohibitively expensive for UWB applications. We developed two different sub-sampling techniques, but the two systems suffer numerous shortcomings: low throughput, non-robustness, non-linearity. A third system is introduced that achieve both high accuracy and high through-put. Changes in the detection algorithm and the frame synchronization are developed to accommodate …

A Low-Power, Reconfigurable, Pipelined Adc With Automatic Adaptation For Implantable Bioimpedance Applications, Terence Cordell Randall

Doctoral Dissertations

Biomedical monitoring systems that observe various physiological parameters or electrochemical reactions typically cannot expect signals with fixed amplitude or frequency as signal properties can vary greatly even among similar biosignals. Furthermore, advancements in biomedical research have resulted in more elaborate biosignal monitoring schemes which allow the continuous acquisition of important patient information. Conventional ADCs with a fixed resolution and sampling rate are not able to adapt to signals with a wide range of variation. As a result, reconfigurable analog-to-digital converters (ADC) have become increasingly more attractive for implantable biosensor systems. These converters are able to change their operable resolution, sampling …

In-Line Microfluidic Particle Preconcentrator And Detector For Continuous Flow Monitoring, Quan Yuan

Doctoral Dissertations

This dissertation presents the design and prototyping of three in-line microfluidic devices for continuous monitoring of particulate flows. The three devices are AC electrokinetic (ACEK) and acoustic sample preconcentration techniques for resettable particle enrichment, and an in-line somatic cell counter for mastitis monitoring.

For the ACEK preconcentrator, ACEK is a new and promising technique to manipulate micro/bio-fluid and particles. There are many advantages over other techniques, such as low applied voltage, low cost, portability and notable biocompatibility of lab-on-a-chip (LOC) device. We successfully developed a 3D multi-level electrode platform to extract bioparticles via AC electroosmosis (ACEO) and negative Dielectrophoresis (DEP). …

An Analog Vlsi Deep Machine Learning Implementation, Junjie Lu

Doctoral Dissertations

Machine learning systems provide automated data processing and see a wide range of applications. Direct processing of raw high-dimensional data such as images and video by machine learning systems is impractical both due to prohibitive power consumption and the “curse of dimensionality,” which makes learning tasks exponentially more difficult as dimension increases. Deep machine learning (DML) mimics the hierarchical presentation of information in the human brain to achieve robust automated feature extraction, reducing the dimension of such data. However, the computational complexity of DML systems limits large-scale implementations in standard digital computers. Custom analog signal processing (ASP) can yield much …

Advanced Studies On Locational Marginal Pricing, Yanli Wei

Doctoral Dissertations

The effectiveness and economic aspect of Locational Marginal Price (LMP) formulation to deal with the power trading in both Day-Ahead (DA) and Real-Time (RT) operation are the focus of not only the system operator but also numerous market participants. In addition, with the ever increasing penetration of renewable energy being integrated into the grid, uncertainty plays a larger role in the process of market operation. The study is carried out in four parts.

In the first part, the mathematical programming models, which produce the generation dispatch solution for the Ex Post LMP, are reviewed. The existing approach fails to meet …

Vehicle-To-Grid (V2g) Reactive Power Operation Analysis Of The Ev/Phev Bidirectional Battery Charger, Mithat Can Kisacikoglu

Doctoral Dissertations

More battery powered electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs) will be introduced to the market in 2013 and beyond. Since these vehicles have large batteries that need to be charged from an external power source or directly from the grid, their charging circuits and grid interconnection issues are garnering more attention.

It is possible to incorporate more than one operation mode in a charger by allowing the power to flow bidirectionally. Usually, the bidirectional power transfer stands for two-way transfer of active power between the charger and the grid. The general term of sending active power from …

A Low-Power, Highly Stabilized Three-Electrode Potentiostat Using Subthreshold Techniques, Melika Roknsharifi

Doctoral Dissertations

Implantable micro- and nano- sensors and implantable microdevices (IMDs) have demonstrated potential for monitoring various physiological parameters such as glucose, lactate, CO₂ [carbon dioxide], pH, etc. Potentiostats are essential components of electrochemical sensors such as glucose monitoring devices for diabetic patients. Diabetes is a metabolic disorder associated with insufficient production or inefficient utilization of insulin. The most important role of this enzyme is to regulate the metabolic breakdown of glucose generating the necessary energy for human activities. Diabetic patients typically monitor their blood glucose levels by pricking a fingertip with a lancing device and applying the blood to a …

A Charge-Recycling Scheme And Ultra Low Voltage Self-Startup Charge Pump For Highly Energy Efficient Mixed Signal Systems-On-A-Chip, Chandradevi Ulaganathan

Doctoral Dissertations

The advent of battery operated sensor-based electronic systems has provided a pressing need to design energy-efficient, ultra-low power integrated circuits as a means to improve the battery lifetime. This dissertation describes a scheme to lower the power requirement of a digital circuit through the use of charge-recycling and dynamic supply-voltage scaling techniques. The novel charge-recycling scheme proposed in this research demonstrates the feasibility of operating digital circuits using the charge scavenged from the leakage and dynamic load currents inherent to digital design. The proposed scheme efficiently gathers the “ground-bound” charge into storage capacitor banks. This reclaimed charge is then subsequently …

Characterization And Implementation Of An Injection Locked Frequency Divider Based On Relaxation Oscillator, Kai Zhu

Doctoral Dissertations

There has been a dramatic increase in wireless awareness among the user community in the past few years. As the wireless communication devices require more integration in terms of both hardware and software, the low-power integrated circuit (IC) solution has gained higher dedication and will dominate in the future radio-frequency IC (RFIC) design. Complementary Metal-Oxide Semiconductor (CMOS) process is extremely attractive for such applications because of its low cost and the possibility to integrate baseband and high frequency circuits on the same chip. The transceiver is often the most power-hungry block in a wireless communication system. The frequency divider (prescaler) …

Real-Time Selective Harmonic Minimization For Multilevel Inverters Using Genetic Algorithm And Artificial Neural Network Angle Generation, Faete Jacques Teixeira Filho

Doctoral Dissertations

This work approximates the selective harmonic elimination problem using Artificial Neural Networks (ANN) to generate the switching angles in an 11-level full bridge cascade inverter powered by five varying DC input sources. Each of the five full bridges of the cascade inverter was connected to a separate 195W solar panel. The angles were chosen such that the fundamental was kept constant and the low order harmonics were minimized or eliminated. A non-deterministic method is used to solve the system for the angles and to obtain the data set for the ANN training. The method also provides a set of acceptable …

Design And Control Of High Power Density Motor Drive, Dong Jiang

Doctoral Dissertations

This dissertation aims at developing techniques to achieve high power density in motor drives under the performance requirements for transportation system. Four main factors influencing the power density are the main objects of the dissertation: devices, passive components, pulse width modulation (PWM) methods and motor control methods.

Firstly, the application of SiC devices could improve the power density of the motor drive. This dissertation developed a method of characterizing the SiC device performance in phase-leg with loss estimation, and claimed that with SiC Schottky Barrier Diode the advantage of SiC JFET could benefit the motor drive especially at high temperature. …

Wide-Area Measurement Application And Power System Dynamics, Lang Chen

Doctoral Dissertations

Frequency monitoring network (FNET) is a GPS-synchronized distribution-level phasor measurement system. It is a powerful synchronized monitoring network for large-area power systems that provides significant information and data for power system situational awareness, real time and post-event analysis, and other important aspects of bulk systems. This work explored FNET measurements and utilized them for different applications and power system analysis.

An island system was built and validated with FNET measurements to study the stability of the OTEC integration. FNET measurements were also used to validate a large system model like the U.S. Eastern Interconnection. It tries to match the simulation …

Design Of Wireless Power Transfer And Data Telemetry System For Biomedical Applications, Ashraf Bin Islam

Doctoral Dissertations

With the advancement of biomedical instrumentation technologies sensor based remote healthcare monitoring system is gaining more attention day by day. In this system wearable and implantable sensors are placed outside or inside of the human body. Certain sensors are needed to be placed inside the human body to acquire the information on the vital physiological phenomena such as glucose, lactate, pH, oxygen, etc. These implantable sensors have associated circuits for sensor signal processing and data transmission. Powering the circuit is always a crucial design issue. Batteries cannot be used in implantable sensors which can come in contact with the blood …

In Situ Preconcentration By Ac Electrokinetics For Rapid And Sensitive Nanoparticle Detection, Kai Yang

Doctoral Dissertations

Reducing cost and time is a major concern in clinical diagnostics. Current molecular diagnostics are multi-step processes that usually take at least several hours or even days to complete multiple reagents delivery, incubations and several washing processes. This highly labor-intensive work and lack of automation could result in reduced reliability and low efficiency. The Laboratory-on-a-chip (LOC), taking advantage of the merger and development of microfluidics and biosensor technology, has shown promise towards a solution for performing analytical tests in a self-contained and compact unit, enabling earlier and decentralized testing. However, challenges are to integrate the fluid regulatory elements on a …

A High -Temperature, High-Voltage, Fast Response Time Linear Regulator In 0.8um Bcd-On-Soi, Chia Hung Su

Doctoral Dissertations

The sale of hybrid electric vehicles (HEVs) has increased tenfold from the year 2001 to 2009 [1]. With this the demand for high temperature electronics has also increased dramatically making, high temperature electronics for HEV applications desirable in the engine compartment, power train, and brakes where the ambient temperature normally exceeds 150°C. Power converters (i.e. DC-DC converter, DC-AC inverter) inside the HEVs require gate drivers to control the power switches. An integrated gate driver circuit has been realized in 0.8-um BCD-on-SOI process. This gate driver IC needs a step-down voltage regulator to convert the unregulated high input DC voltage (VDDH) …

A Novel Frequency Based Current-To-Digital Converter With Programmable Dynamic Range, Xiaoyan Yu

Doctoral Dissertations

This work describes a novel frequency based Current to Digital converter, which would be fully realizable on a single chip.

Biological systems make use of delay line techniques to compute many things critical to the life of an animal. Seeking to build up such a system, we are adapting the auditory localization circuit found in barn owls to detect and compute the magnitude of an input current.

The increasing drive to produce ultra low-power circuits necessitates the use of very small currents. Frequently these currents need to accurately measured, but current solutions typically involve off-chip measurements. These are usually slow, …

Reconfigurable Rf Front End Components For Multi-Radio Platform Applications, Chunna Zhang

Doctoral Dissertations

The multi-service requirements of the 3G and 4G communication systems, and their backward compatibility requirements, create challenges for the antenna and RF front-end designs with multi-band and wide-band techniques. These challenges include: multiple filters, which are lossy, bulky, and expensive, are needed in the system; device board size limitation and the associated isolation problems caused by the limited space and crowd circuits; and the insertion loss issues created by the single-pole-multi-through antenna switch.

As will be shown, reconfigurable antennas can perform portions of the filter functions, which can help solve the multiple filters problem. Additionally, reconfigurable RF circuits can decrease …

Low-Voltage Analog Circuit Design Using The Adaptively Biased Body-Driven Circuit Technique, Stephen Christopher Terry

Doctoral Dissertations

The scaling of MOSFET dimensions and power supply voltage, in conjunction with an increase in system- and circuit-level performance requirements, are the most important factors driving the development of new technologies and design techniques for analog and mixed-signal integrated circuits. Though scaling has been a fact of life for analog circuit designers for many years, the approaching 1-V and sub-1-V power supplies, combined with applications that have increasingly divergent technology requirements, means that the analog and mixed-signal IC designs of the future will probably look quite different from those of the past. Foremost among the challenges that analog designers will …