Engineering Commons^™

Speech Enhancement By Exploiting The Baseband Phase Structure Of Voiced Speech For Effective Non-Stationary Noise Estimation, Sanjay Patil

All Theses

Speech enhancement is one of the most important and challenging issues in the speech communication and signal processing field. It aims to minimize the effect of additive noise on the quality and intelligibility of the speech signal. Speech quality is the measure of noise remaining after the processing on the speech signal and of how pleasant the resulting speech sounds, while intelligibility refers to the accuracy of understanding speech. Speech enhancement algorithms are designed to remove the additive noise with minimum speech distortion.The task of speech enhancement is challenging due to lack of knowledge about the corrupting noise. Hence, the …

Adaptive Transmission For Ofdm, Michael Juang

All Theses

To respond to dynamic channel conditions caused by fading, shadowing, and other time-varying disturbances, orthogonal frequency division multiplexing (OFDM) packet radio systems should adapt transmission parameters on a packet-by-packet basis to maintain or improve performance over the channel. For this to be possible, there are three key ideas that must be addressed: first, how to determine the subchannel conditions; second, which transmission parameters should be adapted; and third, how to adapt those parameters intelligently. In this thesis, we propose a procedure for determining relative subchannel quality without using any traditional channel measurements. Instead, statistics derived solely from subcarrier error counts …

Bite Detection And Differentiation Using Templates Of Wrist Motion, Soheila Eskandari

All Theses

We introduce a new algorithm of bite detection during an eating activity based on template matching. The algorithm uses a template to model the motion of the wrist over a 6-second window centered on the time when a person takes a bite. We also determine if different types of bites (for example food vs. drink, or using different types of utensils) have different wrist motion templates. This method is implemented on 22,383 bites and 5 different types of templates are built. We then describe a method to recognize different types of bites using the set of templates. The obtained accuracy …

Design Of An Optical Position Sensor For Microfiber Actuators, Luxi Cheng

All Theses

This thesis introduces a new type of sensor that detects the position information of a paramagnetic microfiber and transforms it to computational electrical signal. The original purpose of the sensor is to solve the problem of feedback signal detection of the microfiber control system, which is the problem of detecting the position information for the microfiber. The microfiber will be presented as the experimental object of this sensor to test its capability. A novel optical based approach is used to transfer the position signal to a computer scrutable signal for further analysis.

The purpose of the sensor design comes from …

A Probabilistic Analysis Of Islanding Effects In A Modeled Distribution System With Renewable Resources, Paul Gooding

All Theses

For this research, an investigation was undertaken regarding the inclusion of renewable resources into the distribution system. This incorporated the increasing prevalence of solar and wind resources, as well as the development of islanding capabilities within distribution systems.

Fabrication And Characterization Of Radio-Frequency Sensors For Liquid Material Detection, Yuxi He

All Theses

This thesis presents a series of studies on fabrication and characterization of radio-frequency (RF) sensors. In the light of Electromagnetics and Transmission Line Theory, we designed multiple RF sensors with different detection capability emphasis and used them to detect various materials, especially liquid samples and materials in solutions such as dielectric thin films, confined liquids, red blood cells, and malarial pigments (hemozoin). Most sensors were fabricated under clean room environment following the standard process protocols. Proper process developments were also made to achieve special structures and functionalities of our novel sensors. Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) …

Analytical Evaluation Of Adaptive Transmission Protocols For Markov Models Of Channels With Fading And Moderate Shadowing, Sneha Latha Kottapalli

All Theses

Adaptive transmission protocols are often employed to communicate over wireless channels with fading and other time-varying propagation losses. The protocols compensate for the propagation losses and maintain high throughput by adjusting transmission parameters in response to the channel variations. Performance evaluations for practical adaptive transmission protocols typically require simulation of both the time-varying processes and the procedure by which the protocol derives information about the channel quality. In this thesis, we develop an analytical method to evaluate the performance of two practical protocols, an adaptive coding protocol and an adaptive modulation and coding protocol, which rely on statistics derived from …

Reverse Engineering: Wimax And Ieee 802.16e, Katherine Cameron

All Theses

Wireless communications is part of everyday life. As it is incorporated into new products and services, it brings additional security risks and requirements. A thorough understanding of wireless protocols is necessary for network administrators and manufacturers. Though most wireless protocols have strict standards, many parts of the hardware implementation may deviate from the standard and be proprietary. In these situations reverse engineering must be conducted to fully understand the strengths and vulnerabilities of the communication medium.
New 4G broadband wireless access protocols, including IEEE 802.16e and WiMAX, offer higher data rates and wider coverage than earlier 3G technologies. Many security …