Engineering Commons^™

Modified Diamond Dipole Antenna For Ultra Wideband Communications Using Finite Difference Time Domain Method, Srinivas Desamsetty

FIU Electronic Theses and Dissertations

The aim of this thesis is to analyze and design ultra wideband antennas for personal communication devices using Finite Difference Time Domain (FDTD) method. Initially diamond dipole, an ultra wideband antenna is selected from the literature and analyzed. The shape of the diamond dipole is modified in such a way that the straight-line base of the two triangular arms (near the feed) is replaced with an arc. The resulting antenna is named as modified diamond dipole. Performance is observed by varying radius of curvature of base of triangular arms (for constant flare angle) and by varying flare angle (for constant …

Speaker Recognition Using Multiple Parametric Self-Organizing Maps, Pablo Gomez

FIU Electronic Theses and Dissertations

Speaker Recognition is the process of automatically recognizing a person who is speaking on the basis of individual parameters included in his/her voice. This technology allows systems to automatically verify identify in applications such as banking by telephone or forensic science.

A Speaker Recognition system has the following main modules: Feature Extraction and Classification.

For feature extraction the most commonly used techniques are MEL-Frequency Cepstrum Coefficients (MFCC) and Linear Predictive Coding (LPC). For classification and verification, technologies such as Vector Quantization (VQ), Hidden Markov Models (HMM) and Neural Networks have been used.

The contribution of this thesis is a new …

High Performance Shift Invariant Motion Estimation And Compensation In Wavelet Domain Video Compression, Weiting Cai

FIU Electronic Theses and Dissertations

The contributions of this dissertation are in the development of two new interrelated approaches to video data compression:

1) A level-refined motion estimation and subband compensation method for the effective motion estimation and motion compensation.

2) A shift-invariant sub-decimation decomposition method in order to overcome the deficiency of the decimation process in estimating motion due to its shift-invariant property of wavelet transform.

The enormous data generated by digital videos call for an intense need of efficient video compression techniques to conserve storage space and minimize bandwidth utilization. The main idea of video compression is to reduce the interpixel redundancies inside …

Management Of Remote Field Instrumentation Via The Internet, Victor A. Acuña

FIU Electronic Theses and Dissertations

Supervisory Control & Data Acquisition (SCADA) systems are used by many industries because of their ability to manage sensors and control external hardware. The problem with commercially available systems is that they are restricted to a local network of users that use proprietary software. There was no Internet development guide to give remote users out of the network, control and access to SCADA data and external hardware through simple user interfaces.

To solve this problem a server/client paradigm was implemented to make SCADAs available via the Internet. Two methods were applied and studied: polling of a text file as a …

A Multi-Sensor Sonar System For Indoor Range Measurement As A Navigational Aid For The Blind, Maroof Haider Choudhury

FIU Electronic Theses and Dissertations

This project involved the design, implementation and testing of a multi-directional range measurement system for indoor applications, as an independent sensing module for a navigational tool for blind individuals. The system provides real-time distance measurements to the closest surrounding obstacles in six radial directions, and a North direction indication. Custom hardware and software were developed to interface six ultrasonic ranging modules and a digital compass to a PIC16F77 microcontroller. A multi-directional range measuring technique appropriate for this setup was identified experimentally. The final product of this project is a navigational instrument integrating the custom hardware and software, a portable PC, …

A Mathematical Resolution To Log Transformations And The Binning Effect In Applied Processing Of Data In Flow Cytometry, Vidal J. Patricio

FIU Electronic Theses and Dissertations

This dissertation develops a new mathematical approach that overcomes the effect of a data processing phenomenon known as "histogram binning" inherent to flow cytometry data. A real-time procedure is introduced to prove the effectiveness and fast implementation of such an approach on real-world data. The histogram binning effect is a dilemma posed by two seemingly antagonistic developments: (1) flow cytometry data in its histogram form is extended in its dynamic range to improve its analysis and interpretation, and (2) the inevitable dynamic range extension introduces an unwelcome side effect, the binning effect, which skews the statistics of the data, undermining …

Analysis Of The Lateral Diffuse Metal-Oxide Semiconductor (Ldmos) Power Amplifier For Cellular Base Stations, Waldack Bonhome

FIU Electronic Theses and Dissertations

The primary purpose of this thesis was to present a theoretical large-signal analysis to study the power gain and efficiency of a microwave power amplifier for LS-band communications using software simulation. Power gain, efficiency, reliability, and stability are important characteristics in the power amplifier design process. These characteristics affect advance wireless systems, which require low-cost device amplification without sacrificing system performance.

Large-signal modeling and input and output matching components are used for this thesis. Motorola's Electro Thermal LDMOS model is a new transistor model that includes self-heating affects and is capable of small-large signal simulations. It allows for most of …