Engineering Commons^™

Equalization Of A Non-Linear Phase Of A Low-Pass Filter, Rabih Khodor

Dissertations and Theses

In practice, an IIR filter can distort the information content of the signal because of its inherent non-linear phase characteristics introduced through the design of the filter. If the the receiver of the signal is the human ear, e.g., when a speech or music signal is to be processed, phase distortion is quite tolerable. But, in other applications it can be rejected as phase characteristics is required to be fairly linear. Applications of this type include data transmission, where the signal is to be interpreted by digital hardware, and image processing, where the signal is used to reconstruct an image …

An Asic Power Analysis System For Digital Cmos Design, Du Van Nguyen

Dissertations and Theses

Consumers demand for products with ever-increasing functionality, performance, and longer battery life is making low power a critical factor in most system designs. Lower-power designs are less expensive to produce, more reliable, and cost less to operate - factors which create a real competitive advantage. As a result, ASIC designers are demanding better ways to analyze the power of their designs.

In this thesis, an ASIC Power Analysis System (APAS) is developed. APAS is an interactive simulation-based power analysis tool. Using a non-intrusive design technique, APAS can dynamically "snap on" to an existing simulation environment. APAS currently supports three ASIC …

The Multiple Pool Migrating Worker Paradigm : A Distributed System Framework And Model, Cynthia Ann Stanley

Dissertations and Theses

A network of workstations (NOW) can provide an inexpensive and effective distributed processing platform. The purpose of this thesis is two-fold, providing a methodology for distributed computing on a NOW first, and providing a model to predict and monitor performance second. The Multiple Pool-Migrating Worker (MPMW) paradigm uses multiple job pools to divide up tasks and migrating workers to balance the work load. The MPMW paradigm is a quick and efficient way of implementing problems using distributed processing without extensive knowledge of parallel programming. A model describing the MPMW paradigm is developed using queuing theory and Mean Value Analysis techniques. …

Analysis And Optimization Of A Banyan Based Atm Switch By Simulations, Syed Sohel Hussain

Dissertations and Theses

Asynchronous Transfer Mode (ATM) is proposed technology to create a broadband (high speed) packet switching network capable of transporting wide variety of services including voice, video and data in an integrated manner. The main concern in designing the switching fabrics used in this technology are speed, throughput, delay and variance of delay. We analyze the performance by simulations of ATM switch based on Banyan network in the uniform traffic condition.

We compare the analytical results obtained from three-state model Yan and Jenq to the simulation results. Based on observation of simulation results, we propose non-blocking first stage (NBFS) to increase …

Demodulation Of Narrowband Radio Frequency Signals By Aliasing Sampling, Chun-Ching Lin

Dissertations and Theses

The objective of this thesis is to study the demodulation of narrowband radio frequency signals by aliasing sampling in order to reduce the sampling rate. The spectrum can be recreated at the lower frequency position by aliasing sampling. However, if the sampling rate is deviated from the desired one, error will occur. The sensitivity to the frequency error of aliasing sampling is studied.

One main reason of the deviation of the sampling rate is the frequency drifting of the local oscillator. Being able to compensate the oscillator drifting errors inexpensively, automatic frequency control (AFC) loops are important at receivers. Two …

Adaptive Color Correlation Of Knots In Wood Images And Weighted-Value Product Selection Methods In A Machine Vision System, John Robert Goulding

Dissertations and Theses

The biggest obstacle to robust color image processing of wood is in developing a color model that represents all possible defect colors. When the color model is too general or too specific, defect recognition fails because too many or too few non-defect pixels match the model, respectively. Because a color image of wood contains far more clear and clear-grain colored pixels than grain-knot and knot colored pixels, it is beneficial to first statistically identify and remove the clear and clear-grain colors and to use the accumulated data to simultaneously enhance and normalize the remaining grainknot and knot colored pixels. This …

Design Of A Second-Order Filter Using The GM-C Technique, Girish Chandrasekaran

Dissertations and Theses

This thesis deals with the design, layout, fabrication, testing and characterization of a second-order filter (biquad) using the transconductance-C (g_m-C) technique. The biquad was designed to realize the four filter functions - lowpass, highpass, bandpass and notch - by appropriate choice of input and output terminals and element values. The tunable range of frequencies for the biquad was designed to be 18-59MHz. The quality factor of the biquad was designed to be tunable from approximately 1/3 to 3. The filter was designed in LEVEL2 SPICE, laid out using MAGIC, and the circuit was fabricated using MOSIS's …

Design And Implementation Of A Model For Authoring And Presenting Interactive Multimedia Documents, Vibha Mukul Nayyar

Dissertations and Theses

Multimedia technology enables direct manipulation of multiple media such as text, image, audio, and video, all integrated into one entity - the multimedia document. Interactive multimedia documents integrate text, images and continuous media such as audio and video, treat them as objects to be presented for a certain duration, and allow users to interact with the presentation. Authoring and presenting interactive multimedia documents imposes new requirements on document representation. We designed the interactive timeline model (ITM) for authoring and presenting interactive multimedia documents. We implemented the model and created a playback tool using the scripting language Tcl.

ITM uses an …

Circuit Implementation Of A High-Speed Continuous-Time Current-Mode Field Programmable Analog Array (Fpaa), Osama K. Shana'a

Dissertations and Theses

The growing interest in programmable analog circuits has led to the development of Field Programmable Analog Arrays (FPAAs). An FPAA consists of: 1) a programmable cell that can be reconfigured to perform several analog functions. 2) an architecture that interconnects a number of copies of the programmable cell.

In this thesis, the full monolithic circuit implementation of the analog part of the programmable cell is presented. Chapter I gives an introduction to the idea of FPAA and introduces the FPAA architecture and the cell block diagram. Chapter II deals with the design and verification of a differential current-mode four-quadrant multiplier. …

Layout Synthesis For Datapath Designs, Naveen Buddi

Dissertations and Theses

As datapath chips such as microprocessors and digital signal processors become more complex, efficient CAD tools that preserve the regularity of datapath designs and result in small layout area are required. The standard-cell placement techniques ignore the regularity of datapath designs and hence give inefficient layouts. This has necessitated the development of new techniques for datapath module placement. We developed a layout synthesis tool DataPathLAYOUT, for the bit-slice datapath logic designed using standard-cell libraries. We developed fast and area efficient heuristics for placing the cells in a bit-slice such that the regularity of datapath circuits is preserved and the number …

Efficient Buffer Allocation Scheme For Bursty Traffic In Atm Networks Using Fast Reservation Protocol, Nikhil Mukund Deshpande

Dissertations and Theses

One of the major problems in the realization of ATM is traffic management, in particular, the resource allocation for an efficient network. Many approaches to the bandwidth management problems [2] and buffer management problems have been proposed. Boyer [10] suggested a "Fast Bandwidth Reservation" protocol, while Turner [2] applied the same technique to the buffer allocation for the bursty traffic. In this thesis, we extend Turner's scheme in order to make it more efficient with respect to buffer allocation. We define a new parameter "Reduction Factor'', which has the potential of saving a significant amount of buffer space in a …

Nonlinearities In The Base Emitter Junction Of Heterojunction Bipolar Transistors, Oliver Woywode

Dissertations and Theses

The nonlinear behaviour of the base emitter junction in HBTs is investigated. Nonlinearities cause troublesome distortion and intermodulation of signals and raise the bit error rate. They are therefore a key issue in microwave communication systems. Hewlett-Packard's Microwave Design System (MDS) software package has been used to simulate these phenomena. The simulation results are verified by an analytical method called nonlinear current method which is a derivative of the Volterra series approach. With the aid of this method new analytical expressions are derived that provide insight into the subtleties of nonlinear phenomena. These expressions are evaluated by the program MAPLE …

Jitter And Wander Reduction For A Sonet Ds3 Desynchronizer Using Predictive Fuzzy Control, Kevin Blythe Stanton

Dissertations and Theses

Excessive high-frequency jitter or low-frequency wander can create problems within synchronous transmission systems and must be kept within limits to ensure reliable network operation. The emerging Synchronous Optical NETwork (SONET) introduces additional challenges for jitter and wander attenuation equipment (called desynchronizers) when used to carry payloads from the existing Plesiochronous Digital Hierarchy (PDH), such as the DS3. The difficulty is primarily due to the large phase transients resulting from the pointer-based justification technique employed by SONET (called Pointer Justification Events or PJEs). While some previous desynchronization techniques consider the buffer level in their control actions, none has explicitly considered wander …