Engineering Commons^™

A Frequency-Modulated Continuous Wave-Based Boundary Detection System For Determination Of Monitoring Region For An Indoor Ultra-Wideband Short Range Radar-Based Eldercare Monitoring System, Wilson Tang

Master's Theses

Falls are a cause of concern for the elderly since it can render a person immobile. A monitoring system can summon immediate aid by the automatic detection of fall events. The application of ultra-wideband (UWB) signals for a monitoring system was chosen due to its unique characteristics such as wide spectrum, immunity to interference, penetrability, and application for the detection of people. Part of this monitoring system is boundary detection with the purpose of isolating the location of fall events and to function as a mask to define an area of interest. A study of various localizing methods using measurements …

An Investigation Into Ultrasonic Communication For Near-Body Networks, Eric Joshua Escudero Jr., Gursewak Singh Rai

Electrical Engineering

The following report presents a study of body-area, free-space ultrasonic communication system. Two analog communication systems are investigated. The initial communications system setup relies upon the amplitude modulation (AM) techniques to transmit the signal. Such a system is prone to noise since the amplitude of the signal is directly affected by distance and the signal strength will deteriorate. The secondary communication system involves utilizing frequency modulation (FM). This method avoids the issue of losing information due to amplitude deterioration, but encounters delay issues. The main hardware components used in the approach outlined include ultrasonic transducers (UTs) used for both transmitting …

Programmable Household Led Light Fixture, Jordan Locano

Electrical Engineering

This report details the development and construction of a LED light fixture to be used for household lighting. This document details background information, design ideas, project specifications, production, assembly, testing, and conclusions involved with this project. The goals of this project is to design and build a cost-effective replacement for traditional room lighting that can perform better and last longer than traditional methods.

Rem Sleep Alarm, Shaun Kelsey, Brendon Soltis

Electrical Engineering

This paper explores the REM Sleep Alarm project that deals with the sleep cycle of the average human, and how it affects our ability to function when waking up in the morning.

The purpose of this project is to build a device that has the ability to wake a person up when they will feel the most rested. From research done, it appears that most people feel the most rested when woken up during the REM stage of their sleep cycle. Our goal is to have the device detect when the user is in this stage of sleep, determine how …

Variable Dc Voltage Wall Outlet For The Dc House Project, Michael Detmers, Tyler J. Blauvelt

Electrical Engineering

This senior project report will focus on explaining the design and operation of a variable DC wall outlet for use in the DC house. Testing will include the use of various loads using different input DC voltages not exceeding a maximum output of 90W.

The most important aspects of the outlet are to have a highly-efficient converter efficiency as well as system isolation from the main DC bus on the input. This report will outline the purpose and way of achieving isolation through use of a Flyback DC-DC converter. The user interface is the second significant aspect and details of …

Laser Cursor, Michael Liman

Electrical Engineering

A user controls a cursor on a computer screen using a laser pointer.  A camera picks up the laser pointer’s position and sends the data to the computer to move the cursor in the correct position.

Exercise Bicycle Dc-Dc Converter For The Energy Harvesting From Exercise Machines Project, Ryan Rickard, Logan Stowe

Electrical Engineering

Project is a continuation of previous projects that seek an efficient DC to DC converter for the existing exercise bicycle system created by Mechanical and Electrical Engineering students. This DC-DC converter is to integrate with the wide range of DC voltages produced by the bicycle in order to produce a constant optimal voltage for charging a car battery. This converter will boost voltages when the bicycle outputs below the optimal voltage and buck voltages when above. The converter will take EHFEM one step closer to its overall and final goal of harvesting energy from the exercise machines in Cal Poly’s …

Programmable Solid State 12ax7 Triode Gain Stage, Ian Campbell

Electrical Engineering

This project demonstrates the viability of vacuum tube replacements made from solid state technology and programmable logic. A collection of operational amplifiers, digital converters and a field programmable gate array (FPGA) achieve this goal. The project emulates a 12AX7 vacuum tube triode as it would operate in a Fender Champ guitar amplifier. While the prototype works specifically with the Fender Champ, minor modifications could provide the versatility for operation in different amplifiers, including high end vintage hi-fi equipment. The addition of a micro controller into these amplifiers allows for the use of digital filtering and effects while not requiring modifications …

One-Pin 32 Khz Low-Power Crystal Oscillator, Aaron Plata-Ruiz

Electrical Engineering

This design is a one-pin, 32 kHz, low-power, crystal oscillator suitable for battery-operated systems. The design is based on a design published by Ali E Zadeh, “A Micropower, Battery-Operated, One-Pin Crystal Oscillator”, but redesigned for standard positive power supply configuration, which is suitable for typical n-well CMOS process.

Solar Powered Backpack, Saagar Sabharwal, Tom Poonsopin

Electrical Engineering

One popular motto in electrical engineering today is “going green.” This project will convert the sun’s energy into reusable energy. The purpose of this senior project is to develop a solar powered backpack that can charge certain portable USB devices for students. Many students walk around campus with an iPod or cell phone, which has surely died or ran low on batteries at least once when needed most. This backpack will allow students to charge their devices “on the go.” When students walk or bike around campus, the solar panels attached to the backpack will allow recharging of their portable …

Rfid Techniques For Passive Electronics, Ryan Behr, David Cobos

Electrical Engineering

No abstract provided.

Smooth Ternary Signaling For Deep-Submicron(Dsm) Buses, Robert Endicott Hanson, Ryan Ian Fullerton

Electrical Engineering

This project demonstrates the error mitigating effects of using a three-level “smooth ternary” signal on a Deep-Submicron(DSM) bus with large inter-wire capacitance. An RC circuit used to simulate and exaggerate (for easier testing) the charging and discharging of the DSM bus. An encoder stage translates binary input data into a three-level signal before sending it to the bus. A decoder stage then translates the three-level signal back to binary that is ideally identical to the original signal. Our results show that the three-level signal has much cleaner transitions than a traditional binary signal. A few glitches that appeared when decoding …

Design And Simulation Of V2g Bidirectional Inverter And Dc-Dc Converter, Allan Agatep, Mason Ung

Electrical Engineering

As plug-in hybrid electric vehicles (PHEV) become more popular, the utility companies are forced to feed the grid more electricity. However, these PHEVs are capable of providing power to the grid when they are parked serving as ancillary systems for grid regulation (V2G). Using a system based on photovoltaic (PV) technology, a design for a bidirectional inverter with LCL filter, and a bidirectional dc-dc with a constant current controller, was constructed using LTspice. Various papers were researched and analyzed to determine applicable designs for components. Simulations show the designs are capable of bidirectional power transfer. ETAP simulations show that delivering …

Variability Of Electroluminescent Displays, Christopher (C.) Michael Shedd, Nathan Ostrout

Graphic Communication

No abstract provided.

Development Of A Cubesat Instrument For Microgravity Particle Damper Performance Analysis, John Trevor Abel

Master's Theses

Spacecraft pointing accuracy and structural longevity requirements often necessitate auxiliary vibration dissipation mechanisms.  However, temperature sensitivity and material degradation limit the effectiveness of traditional damping techniques in space.  Robust particle damping technology offers a potential solution, driving the need for microgravity characterization.   A 1U cubesat satellite presents a low cost, low risk platform for the acquisition of data needed for this evaluation, but severely restricts available mass, volume, power and bandwidth resources.  This paper details the development of an instrument subject to these constraints that is capable of capturing high resolution frequency response measurements of highly nonlinear particle damper dynamics.

Bridgeless Active Power Factor Correction Using A Current Fed Push Pull Converter, Jeramie Seth Bianchi

Master's Theses

ABSTRACT

Bridgeless Active Power Factor Correction

Using a Current Fed Push Pull Converter

Jeramie Seth Bianchi

Switched Mode Power Supplies have become increasingly popular for efficient methods of delivering power to an assortment of electronic devices. This thesis proposes a method of using a current fed push pull converter to provide active power factor correction and rectification in a single stage. While most AC-DC converters utilize a bridge rectifier to convert AC-DC and then perform DC-DC conversion, the proposed circuit will utilize its output diodes to perform rectification, thus eliminating the need for a bridge rectifier. This circuit will also …

Project 308: Augmented Reality Mario Kart, Joseph Abad, David Allender, Joryl Calizo, Ryan Gaspar, Gavin Lee

Computer Engineering

Mario Kart is a popular go-kart racing game developed by Nintendo. The premise of the game is simple: drive a go-kart along a racetrack and reach the finish line before the other players. What makes this game unique, however, is the inclusion of weapons, traps, and other projectiles that a player can use to gain an advantage in the race. We have taken on the challenge of not only recreating this amazing game, but using the art of Augmented Reality to fully immerse the player in the full experience. Rather than play the game on a television screen with a …

Off-Grid Public Lighting System – Design And Characterization Of An Led Luminaire, Quanghuy Le

Master's Theses

The technological advances made in the photovoltaic industry have led to a vast exploration of self-sustaining systems.  As the consumer demand for electricity rises from increasing population and development of existing technologies, new practices in system designs are required to relieve the impact on the electrical grid.

This thesis delves into a developing concept of using photovoltaic modules for roadway lighting, with emphasis on establishing the fundamental design for a “spot-lighting” luminaire.  By effectively extinguishing various sections of the luminaire in the absence of pedestrian trafficking, the proposed design and implementation will minimize the prolonged costs, as well as the …

Modeling And Analysis Of The Effects Of Pcb Parasitics On Integrated Dc-Dc Converters, Darwin Domingo Fernandez

Master's Theses

Load transients are prevalent in every electronic device including semiconductor memory, card readers, microprocessors, disc drives, piezoelectric devices, and digitally based systems. They are capable of producing voltage stress, introducing noise, and degrading device functionality. In order to avoid damage to the device, a feedback control loop is implemented with system compensation to regulate the output voltage deviations by the converter. Because designing compensation networks can be rather complicated, DC-DC converters with integrated feedback control topologies help minimize design time and complexity of converter compensation at the expense of design flexibility. This thesis widens the limitations of an integrated DC-DC …

Photovoltaic Emulator Adaptable To Irradiance, Temperature And Panel Specific I-V Curves, Joseph Gamos Durago

Master's Theses

This thesis analyzes the design and performance of a photovoltaic (PV) emulator. With increasing interest in renewable energies, large amounts of money and effort are being put into research and development for photovoltaic systems. The larger interest in PV systems has increased demand for appropriate equipment with which to test PV systems.

A photovoltaic emulator is a power supply with similar current and voltage characteristics as a PV panel. This work uses an existing power supply which is manipulated via Labview to emulate a photovoltaic panel. The emulator calculates a current-voltage (I-V) curve based on the user specified parameters of …

Efficient Packet Delivery In Modern Communication Networks, Nan Wang

Dissertations

Modern communication networks are often designed for diverse applications, such as voice, data and video. Packet-switching is often adapted in today’s networks to transmit multiple types of traffic. In packet-switching networks, network performance is directly affected by how the networks handle their packets. This work addresses the packet-handling issues from the following two aspects: Quality of Service (QoS) and network coding.

QoS has been a well-addressed issue in the study of IP-based networks. Generally, nodes in a network need to be informed of the state of each communication link in order to make intelligent decisions to route packets according to …

Optimizing Resource Allocation In Next-Generation Optical Access Networks, Jingjing Zhang

Dissertations

To meet rapidly increasing traffic demands caused by the popularization of Internet and the spouting of bandwidth-demanding applications, Passive Optical Networks (PONs) exploit the potential capacities of optical fibers, and are becoming promising future-proof access network technologies. On the other hand, for a broader coverage area and higher data rate, integrated optical and wireless access is becoming a future trend for wireless access. This thesis investigates three next-generation access networks: Time Division Multiplexing (TDM) PONs, Wavelength Division Multiplexing (WDM) PONs, and WDM Radio-Over-Fiber (RoF) Picocellular networks.

To address resource allocation problems in these three networks, this thesis first investigates respective …

Digital Image Forensics, Fei Long

Theses

Digital image forensics is a relatively new research field that aims to expose the origin and composition of, and the history of processing applied to digital images. Hence, the digital image forensics is expected to be of significant importance to our modern society in which the digital media are getting more and more popular. In this thesis, image tampering detection and classification of double JPEG compression are the two major subjects studied. Since any manipulation applied to digital images changes image statistics, identifying statistical artifacts becomes critically important in image forensics. In this thesis, a few typical forensic techniques have …

Design And Evaluation Of An Adaptable Vector Coprocessor For Multicores, Timothy William Steele

Theses

Future applications for multi-core processor systems will require increased signal processing power along with increased resource utilization and decreased power consumption. Conservative power consumption will be of paramount importance primarily for battery-powered portable multi-core platforms (e.g., advanced cell phones, tablet computers, etc.). This thesis investigates the robustness, efficiency and effectiveness of vector coprocessor sharing policies in multi-core environments. Vector coprocessor sharing is based on an innovative design for a vector lane that forms the building block for the creation of larger vector coprocessors. This innovative lane design contains a floating-point multiply unit, a floating-point add/subtract unit, a miscellaneous function unit, …

Principal Angles And Principal Azimuths Of Frustrated Total Internal Reflection And Optical Tunneling By An Embedded Low-Index Thin Film, R. M.A. Azzam, F. F. Sudradjat

Electrical Engineering Faculty Publications

The condition for obtaining a differential (or ellipsometric) quarter-wave retardation when p- and s-polarized light of wavelength λ experience frustrated total internal reflection (FTIR) and optical tunneling at angles of incidence ϕ≥ the critical angle by a transparent thin film (medium 1) of low refractive index n1 and uniform thickness d, which is embedded in a transparent bulk medium 0 of high refractive index n0 takes the simple form: −tanh2x=tanδptanδs , in whichx=2πn1(d/λ)(N2sin2ϕ−1)1/2 , N=n0/n1 , and δp , δs are 01 interface Fresnel reflection phase shifts for the pand s polarizations. From this condition, the …

Led Device Having Improved Light Output, Ronald S. Cok, Michael E. Miller

AFIT Patents

A thin-film, white-light-emitting diode device includes a reflective, conductive thin-film structure and a semi-transparent, conductive thin-film structure. One or more thin-film layers are formed between the reflective and semi-transparent conductive thin-film structures to form two or more commonly-controlled microcavity structures. The thin-film layers emit white light in response to current provided by the conductive thin-film structure. Each of the two or more commonly-controlled microcavity structures has a different resonant frequency within one or more optical cavities and emits light with a smaller spectral range than the spectral range of the white-light-emitting thin-film layer(s). A combination of light emitted from the …

Passive Matrix Electro-Luminescent Display System, Michael E. Miller, John F. Hamilton Jr., Andrew D. Arnold

AFIT Patents

A passive matrix, electro-luminescent display system has a passive matrix, electro-luminescent display having an orthogonally oriented array of column and row electrodes and an electro-luminescent layer located between the electrodes at the intersection of each column and row electrode forming an individual light-emitting element. Drivers provide separate signals at different times to different groups of row electrodes within the array of row electrodes; wherein the row electrodes of each group simultaneously receive at least two different level signals. A display driver receives and processes the input image signal to provide a presharpened image control signal. Column drivers respond to the …

Examination Of Chaotic Signal Encryption And Recovery For Secure Communication Using Hybrid Acousto-Optic Feedback, Monish Ranjan Chatterjee, Mohammed A. Al-Saedi

Electrical and Computer Engineering Faculty Publications

Generation of chaos from acousto-optic (A-O)Bragg cell modulators with an electronic feedback has been studied for over 3 decades. Since an acousto-optic Bragg cell with zeroth- and first-order feedback exhibits chaotic behavior past the threshold for bistability, such a system was recently examined for possible chaotic encryption of simple messages (such as a low-amplitude sinusoidal signal) applied via the bias input of the sound cell driver. Subsequent recovery of the message signal was carried out via a heterodyne-type strategy employing a locally generated chaotic carrier, with threshold parameters matched to the transmitting Bragg cell.

In this paper, we present numerical …

Development Of A Reconfigurable Multi-Faceted Communications Device Using Partial Dynamic Reconfiguration, Richard Dunkley

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Supporting a variety of communication protocols has typically required extensive hard- ware and Input/Output (I/O) interfaces targeting each protocol specifically. Recent designs in the past ten years have created more dynamic approaches by using Field Programmable Gate Arrays (FPGAs) and embedded hardware to implement or simulate previous hardware I/O designs. With the constant increase in FPGA and embedded technologies the capabilities of dynamic implementations have expanded. This report addresses the design of an up-to-date reconfigurable multi-faceted embedded device targeting recent technological advances in FPGAs.

Elliptical Machine Dc-Dc Converter For The Energy Harvesting From Exercise Machines Project, Greg Hollister

Electrical Engineering

Designing a DC/DC Converter for the Cal Poly Energy Harvesting from Exercise Machines project requires special attention to the unique operating characteristics of the source and the load. An elliptical machine powered by a person exercising comprises the source, while an AC Inverter makes up the load. This project attempts to integrate the two devices with a custom DC/DC Converter in order to ultimately deliver power back into the power grid.