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Fpga-Based Experiment Platform For Hardware-Software Codesign And Hardware Emulation, Yajuvendra Nagaonkar May 2006

Fpga-Based Experiment Platform For Hardware-Software Codesign And Hardware Emulation, Yajuvendra Nagaonkar

Theses and Dissertations

An FPGA-based experiment platform for hardware-software codesign experiments was developed. The proposed platform would be used by an engineer who can be affiliated with academia, research or industry for codesign experiments or hardware emulation. The platform utilizes a combination of a microcontroller and a FPGA device to enable sufficient flexibility in exploring the design space to implement codesign experiments. The FPGA device operation is integrated with that of the microcontroller to provide an overall embedded solution for codesign experimentations. It is anticipated that the platform will be used in academia for educating the students the concepts of computer architecture and …


Compact Integrated Depolarizer For Interferometric Fiber Optic Gyroscopes, Lixia Li, Jaime Cardenas, Jianhua Jiang, Gregory P. Nordin May 2006

Compact Integrated Depolarizer For Interferometric Fiber Optic Gyroscopes, Lixia Li, Jaime Cardenas, Jianhua Jiang, Gregory P. Nordin

Faculty Publications

We propose an integrated waveguide depolarizer for use in interferometric fiber optic gyroscopes (IFOGs) with single-mode fiber coils. The integrated waveguide depolarizer is based on a Mach-Zender interferometer with polarizing beamsplitters. A waveguide polarizing beamsplitter is designed using multiple air trench structures oriented at the Brewster angle. We also analyze the effect of component imperfections on the degree of polarization achievable with an integrated waveguide depolarizer.


Design Of Compact Polymer Mach-Zender Interferometer And Ring Resonator With Air Trench Structures, Seunghyun Kim, Jianhua Jiang, Gregory P. Nordin May 2006

Design Of Compact Polymer Mach-Zender Interferometer And Ring Resonator With Air Trench Structures, Seunghyun Kim, Jianhua Jiang, Gregory P. Nordin

Faculty Publications

We discuss the design of a compact ring resonator (RR) and Mach-Zehnder interferometer (MZI) in a low-refractive-index-contrast waveguide material system through the use of air trenches. A narrow air trench at the intersection of one input and two output waveguides can function as a high-efficiency splitter, while wider air trenches operate as waveguide bends. We first discuss the design of individual splitters and bends and then show how they can be used to realize a compact MZI and RR. The RR has a footprint of only 70 X 100 um, and its optical efficiency at the drop wavelengths is 86%. …


Solid-State Impact-Ionization Multiplier, Hong-Wei Lee Mar 2006

Solid-State Impact-Ionization Multiplier, Hong-Wei Lee

Theses and Dissertations

This dissertation presents an innovative solid-state current amplifier based on impact-ionization. Unlike avalanche photodetectors which use the same amplification principle, this device can be integrated with any external current source. A discrete amplifier was built on a silicon surface using standard CMOS fabrication processes including lithography, oxidation, ion implantation, diffusion, chemical wet etching, metal deposition, annealing, and rapid thermal processing. Testing was performed by connecting the device to a silicon photodiode, indium-gallium-arsenide photodiodes, and a function generator to demonstrate its compatibility with arbitrary current sources. Current gains above 100 along with pre-amplified leakage currents of less than 10 nA were …


Medium Access Control And Networking Protocols For The Intra-Body Network, Eric Thomas Stucki Mar 2006

Medium Access Control And Networking Protocols For The Intra-Body Network, Eric Thomas Stucki

Theses and Dissertations

Biomedical applications offer an exciting growth opportunity for wireless sensor networks. However, radio frequency communication is problematic in hospital environments that are susceptible to interference in the industrial, scientific, and medical (ISM) bands. Also, RF is inherently insecure as eavesdroppers can easily pick up signals. The Intra-Body Network (IBNet) proposes a novel communication model for biomedical sensor networks. It seeks the convenience of wireless communication while avoiding interference and privacy concerns associated with RF. IBNet's solution is to utilize a subject's own body tissue as a transmission medium. Assuming that transmissions are contained within the body, IBNet solves otherwise complex …


A Framework For An Implantable Wireless Pressure And Volume Sensor Focusing On The Diagnosis And Treatment Of Shunt Failure In Hydrocephalus Patients, Donald Monte Wichern Jan 2006

A Framework For An Implantable Wireless Pressure And Volume Sensor Focusing On The Diagnosis And Treatment Of Shunt Failure In Hydrocephalus Patients, Donald Monte Wichern

Theses and Dissertations

The framework for a permanently implantable wireless compliance sensor was developed and validated using laboratory experiments. The proposed sensor would measure the intracranial pressure and fluid volume in the brain and return this information to a monitoring device. The designed sensor received power remotely from the monitoring device negating the need for an implanted power source. Impedance measurement estimation techniques were suggested, studied and applied to the compliance sensing system. A new impedance measurement technique, accounting for multiple variability in the domain, was developed. An extensive simulation environment was designed and used to develop the laboratory experiments and hardware. The …


Satisficing Negotiations, Wynn C. Stirling, James K. Archibald, Jared C. Hill, F. Ryan Johnson Jan 2006

Satisficing Negotiations, Wynn C. Stirling, James K. Archibald, Jared C. Hill, F. Ryan Johnson

Faculty Publications

Negotiation procedures that are founded on the doctrine of individual rationality, where each participant is committed to maximizing its own satisfaction, are limited in their ability to accommodate the interests of others, and therefore, may unnecessarily constrain the negotiability of a decision maker, particularly in cooperative environments. Satisficing game theory provides a distinct alternative to the hyperrationality of conventional rational choice by waiving reliance on the individual rationality premise and offering an approach to negotiatory decision making that is based on a well-defined mathematical notion of satisficing, or being good enough, that permits the modeling of complex interrelationships between agents. …


Microwave Observations Of Daily Antarctic Sea-Ice Edge Expansion And Contraction Rates, David G. Long, Jeffrey R. Allen Jan 2006

Microwave Observations Of Daily Antarctic Sea-Ice Edge Expansion And Contraction Rates, David G. Long, Jeffrey R. Allen

Faculty Publications

Algorithms for estimating sea-ice extent from remotely sensed microwave sensor data can benefit from knowledge of the "a priori" distribution of the daily expansion and contraction of the sea-ice pack. To estimate the probability distribution of daily Antarctic sea-ice extent change, two independent sea-ice datasets are analyzed: sea-ice extent derived from the QuikSCAT scatterometer and ice concentration estimates from the Special Sensor Microwave/Imager. The daily sea-ice advance and retreat is tracked over a four-year period. The distribution of the daily sea-ice advance/retreat from each sensor is similar and is approximately double-exponential. Daily ice-pack statistics are presented.


Use Of Thermally Induced Higher Order Modes Of A Microcantilever For Mercury Vapor Detection, Gregory P. Nordin, Michael A. George, Ashwini R. Kadam Jan 2006

Use Of Thermally Induced Higher Order Modes Of A Microcantilever For Mercury Vapor Detection, Gregory P. Nordin, Michael A. George, Ashwini R. Kadam

Faculty Publications

We demonstrate the use of thermally induced higher order modes of a microcantilever as an alternate detection technique by studying Au-Hg interactions. The first four thermally induced flexural modes - i.e., the fundamental and first three higher order modes - have been examined for two different Au coatings. In the first case, 50 nm thick Au is sputter deposited along the entire length of a rectangular Si microcantilever. In the second case the Au is confined to a 30 µm length at the tip of the Si microcantilever. In both cases the microcantilever spectral response and deflection has been studied …


Reducing Energy In Fpga Multipliers Through Glitch Reduction - Clock Power And Digit-Serial Addendum, Nathaniel Rollins, Michael J. Wirthlin Jan 2006

Reducing Energy In Fpga Multipliers Through Glitch Reduction - Clock Power And Digit-Serial Addendum, Nathaniel Rollins, Michael J. Wirthlin

Faculty Publications

Sponsorship: NASA. In a previous paper it was shown that reducing the amount of glitches in digital designs can significantly reduce the amount of dynamic power consumption. Pipelined multipliers and a bit-serial multiplier design were used to show this. The paper failed to mention how much of the dynamic power consumption was due to the clock distribution. Also the only digit- serial multiplier digit size investigated was a digit size of 1. This paper addresses the issue of dynamic clocking power and includes results of digit-serial multipliers with larger digit sizes.


Cooperative Forest Fire Surveillance Using A Team Of Small Unmanned Air Vehicles, Randal Beard, David Casbeer, Derek Kingston, Timothy W. Mclain, Sai-Ming Li, Raman Mehra Jan 2006

Cooperative Forest Fire Surveillance Using A Team Of Small Unmanned Air Vehicles, Randal Beard, David Casbeer, Derek Kingston, Timothy W. Mclain, Sai-Ming Li, Raman Mehra

Faculty Publications

This research was supported by NASA under STTR contract No. NNA04AA19C to Scientific Systems Company, Inc (SSCI) and Brigham Young University (BYU), and by AFOSR grants F49620-01-1-0091 and F49620-02-C- 0094. The objective of this paper is to explore the feasibility of using multiple low-altitude, short endurance (LASE) unmanned air vehicles (UAVs) to cooperatively monitor and track the propagation of large forest fires. A real-time algorithm for tracking the perimeter of a fire with an on-board infrared sensor is developed. Using this algorithm, we develop a decentralized multiple-UAV approach to monitoring the perimeter of the fire. The UAVs are assumed to …