Systems and Communications Commons^™

Conductive Concrete For Electromagnetic Shielding – Methods For Development And Evaluation, Aaron P. Krause

Department of Computer Electronics and Engineering: Dissertations, Theses, and Student Research

This research investigates the development and evaluation innovative methods for the use of conductive concrete as an electromagnetic shield. New testing methods are developed to determine the best conductive components to use in the design of a concrete mixture for shielding that shows the best promise. The conductive concrete mixture has the potential to provide electromagnetic shielding that is cost-effective in terms of construction, operation, and maintenance compared to conventional approaches. Two testing methods, Small Sample Testing and Large Slab Testing, are developed based on standardized testing methods that have been modified for the testing of conductive concrete mixtures. As …

Radio Link Analysis And Characterization Of Past And Future Cal Poly Cubesats, Brian Gilbert Tubb

Electrical Engineering

Cal Poly's satellites design team, PolySat, has three satellites in Low Earth Orbit (LEO) and four more planned to launch within the next two years. Radio communication of past and current orbiting satellites has been an exercise in frustration, prompting significant research into the satellite-side of the radio link by several other Senior Projects and Thesis papers. However, minimal effort has been spent on evaluating why these problems were discovered only once the satellites reached orbit. This paper details the downfalls of relying heavily on link budgets and improper long range test setups, then experimentally determines the sensitivity of PolySat's …

Radio Direction Finding Network Receiver Design For Low-Cost Public Service Applications, Marcel Colman Eric Stieber

Master's Theses

A low-cost radio direction finding (RDF) VHF receiver has been investigated for development into a radio direction finding network (RDFN) with a particular focus towards public service and commercial asset tracking applications. The primary design criteria were reproducibility, low-cost, and simplicity such that public service and volunteer organizations can benefit from the technology. Two receiver designs were built and tested to allow for comparison of practicality, cost, and accuracy. A pseudo-Doppler RDF and a time difference of arrival (TDOA) receiver were built as proof-of-concept for a system design based on commercial off-the-shelf (COTS) components. The pseudo-Doppler system is a less …

Design And Analysis Of An Adaptive Asynchronous System Architecture For Energy Efficiency, Brent Michael Hollosi

Graduate Theses and Dissertations

Power has become a critical design parameter for digital CMOS integrated circuits. With performance still garnering much concern, a central idea has emerged: minimizing power consumption while maintaining performance. The use of dynamic voltage scaling (DVS) with parallelism has shown to be an effective way of saving power while maintaining performance. However, the potency of DVS and parallelism in traditional, clocked synchronous systems is limited because of the strict timing requirements such systems must comply with. Delay-insensitive (DI) asynchronous systems have the potential to benefit more from these techniques due to their flexible timing requirements and high modularity. This dissertation …

Energy And Spectral Efficient Wireless Communications, Guoqing Zhou

Graduate Theses and Dissertations

Energy and spectrum are two precious commodities for wireless communications. How to improve the energy and spectrum efficiency has become two critical issues for the designs of wireless communication systems. This dissertation is devoted to the development of energy and spectral efficient wireless communications. The developed techniques can be applied to a wide range of wireless communication systems, such as wireless sensor network (WSN) designed for structure health monitoring (SHM), medium access control (MAC) for multi-user systems, and cooperative spectrum sensing in cognitive radio systems.

First, to improve the energy efficiency in SHM WSN, a new ultra low power (ULP) …

Noise Reduction With Microphone Arrays For Speaker Identification, Zachary Gideon Cohen

Master's Theses

The presence of acoustic noise in audio recordings is an ongoing issue that plagues many applications. This ambient background noise is difficult to reduce due to its unpredictable nature. Many single channel noise reduction techniques exist but are limited in that they may distort the desired speech signal due to overlapping spectral content of the speech and noise. It is therefore of interest to investigate the use of multichannel noise reduction algorithms to further attenuate noise while attempting to preserve the speech signal of interest.

Specifically, this thesis looks to investigate the use of microphone arrays in conjunction with multichannel …

Integration Of Inverted-F Antenna With Solar Cell Substitute, Oisin O’Conchubhair, Patrick Mcevoy, Max Ammann, Giuseppe Ruvio

Conference Papers

A study into the effect of a solar cell lattice on the performance of an Inverted-F antenna is presented. An FR-4 substrate with a lattice of copper electrodes printed on one side and a solid copper ground plane on the other is used to represent a polycrystalline solar cell. The effect of the lattice orientation on the performance of the Inverted-F antenna is discussed.

A 2.45/5.8 Ghz Folded Monopole Antenna For Wlan Applications, Abraham Loutridis, Matthias John, Giuseppe Ruvio, Max Ammann

Conference Papers

A probe-fed printed folded monopole antenna for WLAN applications is presented. The antenna operates at 2.45 GHz and 5.8 GHz, is compact and has omni-directional characteristics in both bands. A parametric study of key geometrical parameters is reported.

Circularly Polarized Terminal Antennas For Emerging Wireless Systems, Max Ammann, Xiulong Bao, Adam Narbudowicz

Conference Papers

Several types of omni-directional Circularly Polarized (CP) antennas are presented, which are employed by three different types of feedlines: Coplanar Waveguide (CPW) fed, Microstrip fed, and Differential-fed, to achieve omni-directional CP performances. The Dual-frequency Omni-directional CP antenna is proposed by using slot and inductor embedded into radiated patches. These omnidirectional CP antennas have potential application on GPS, WLAN and RFID systems.

Constant Conduction Angle Biasing For Class C Monolithic Rf Power Amplifiers, Gursewak Singh Rai

Master's Theses

In modern wireless communication systems, a base station typically serves a few hundred users within its cell coverage. To combat the near-far problem – the situation where a nearby user’s strong cellular signal masks the cellular signal of a faraway user – base stations continually enforce power control. That is, nearby users must lower their transmit power. In CDMA technology, power control can be as large as 70-80dB. At low power outputs, this greatly impacts the performance of the RF power amplifier (PA) in the cellular device. For small RF drives, the magnitude of the output RF current approaches the …

On An Iterative Method For Basis Pursuit With Application To Echo Cancellation With Sparse Impulse Responses, Pratik Shah, Steven L. Grant, Jacob Benesty

Electrical and Computer Engineering Faculty Research & Creative Works

Basis pursuit has been shown to be an effective method of solving inverse problems with a small amount of data when the system to be determined has a sparse representation. Adaptive filters fall under this general category of problems. Here, we use the echo cancellation context to introduce a method of solving the basis pursuit problem with an iterative method based on the proportionate normalized affine projection algorithm (PAPA). Earlier, it has been shown that PAPA can be derived from a basis pursuit perspective. Here we refine the assumptions made in those derivations and show that an iterative form of …

Effect Of Frequency Oversampling And Cascade Initialization On Permutation Control In Frequency Domain Bss, Christopher Osterwise, Steven L. Grant

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a new algorithm for addressing the permutation ambiguity in convolutive blind source separation. the proposed algorithm seeks to prevent permutations by frequency oversampling, and then exploiting the induced correlation between bins. Any remaining permutation is then corrected by beam pattern estimation. Cascade initialization is shown to improve system performance while decreasing processing time, while frequency oversampling is shown to increase performance with slight increases in computational time. the algorithm is proven robust against isotropic noise, producing an SIR improvement of 12.9 dB when the reverberation time is 260 ms, and the signals at the input are only …

Infrared And Intertial Tracking In The Immersive Audio Environment For Enhanced Military Training, Pratik Shah, Ayman Faza, Raghavendra Nimmala, Steven Grant, William Chapin, Robert Montgomery

Psychological Science Faculty Research & Creative Works

The Immersive Audio Environment (IAE) was designed to provide an effective military training facility. It's efficacy at synthesizing sounds from desired directions and also the ability to synthesize moving sounds has been previously reported. This paper discusses the addition of a tracking system to evaluate subject training performance. Numerous tracking systems have been developed for tracking in immersive environments. Some examples include using head mounted web cams, visible light cameras mounted on the support structure, or even single camera tracking as in commercially available entertainment. Our system uses a combination of an existing infrared tracking system and a specially designed …

Development And Implementation Of A Calibration Procedure For Complex Impedance Spectrum Measurements With Applications To Embedded Battery Health Monitoring And Management Systems, William H. Morrison

Master's Theses

Energy storage devices such as rechargeable Lithium ion batteries are assuming an increasingly prominent role in society, covering applications from electric / hybrid electric vehicles to personal portable electronics. In response to this increasing demand, technologies that monitor battery health and remaining useful life have developed. One such system is the Smart Battery Status Monitor (SBSM), developed by the Idaho National Laboratory, Montana Tech and Qualtech Systems, Inc. The SBSM utilizes impedance spectrum measurements using a subsystem called the Impedance Measurement Box (IMB). The impedance measurements are complex quantities (having both a resistive and a reactive component) and are made …

Wireless Networks-On-Chips: Architecture, Wireless Channel, And Devices, David W. Matolak, Avinash Kodi, Savas Kaya, Dominic Ditomaso, Soumyasanta Laha, William Rayess

Faculty Publications

Wireless networks-on-chips (WINoCs) hold substantial promise for enhancing multicore integrated circuit performance, by augmenting conventional wired interconnects. As the number of cores per IC grows, intercore communication requirements will also grow, and WINoCs can be used to both save power and reduce latency. In this article, we briefly describe some of the key challenges with WINoC implementation, and also describe our example design, iWISE, which is a scalable wireless interconnect design. We show that the integration of wireless interconnects with wired interconnects in NoCs can reduce overall network power by 34 percent while achieving a speedup of 2.54 on real …

Active Storage And Ssd Caching In An Object Storage Environment, Michael T. Runde

Master's Theses

The advancing performance and lowering costs required to implement additional processing power on system peripherals such as disk drives are increasingly allowing additional computing ability to be located directly on individual drives. Active Storage attempts to take advantage of this excess by moving some computationally intensive applications directly to the disk drives. This can remove the bottlenecks seen through interconnects between the drives and the CPU of an initiating system as well as remove the need for systems to handle these applications.

The contributions of this thesis are in two areas. The first is the development of a framework designed …

Proximity Study Of A Uwb Directional Conformal Antenna On Water Pipe, Domenico Gaetano, Max Ammann, Patrick Mcevoy, Matthias John, Louise Keating, Frances Horgan

Articles

A preliminary study on the conformal properties of an antipodal exponentially tapered antenna placed on the surface of a flow meter system in the UWB range is presented. It was observed that the water effect can be mitigated by shifting the antenna away from the pipe surface.

3.5 To 30 Mhz Automatic Antenna Impedance Matching System, William Blodgett

Electrical Engineering

Two-way communications using 3 to 30 MHz, high-frequency (HF) radio, also known as shortwave radio, provides worldwide coverage with no infrastructure required between stations. Amateur or “Ham” radio operators apply this advantage to long distance communications and to provide disaster relief communications. Optimum frequencies for long distance propagation are time-of-day variant necessitating an operating frequency range of 3 to 30 MHz. HF half wave dipole antenna length varies from 15 to 150 ft over this range. Fixed-length antenna impedance varies with frequency due to physical dimension dependent capacitance and inductance. Maximum transmitter to antenna power transfer occurs when the transmission …

Spectral Analysis Of Encrypted Chaotic Signals Using Fast Fourier Transforms And Laboratory Spectral Analyzers, Monish Ranjan Chatterjee, Abhinay Kundur

Electrical and Computer Engineering Faculty Publications

The use of acousto-optic chaos, as manifested via first-order feedback in an acousto-optic Bragg cell, in encrypting a message wave and subsequently recovering the message in the receiver using a chaotic heterodyne strategy, has been reported recently [1-3]. In examining the dynamical system analytically using computer simulation, (expected) modulated chaos waveforms are obtained within specified observation windows.

Because of the relatively random nature inherent in chaos waveforms, it is essentially impossible to ascertain from the visual display of the chaotic wave whether a given message signal has in fact modulated the chaotic "carrier". In fact, it has been observed from …

Energy Efficiency Analysis And Optimization On Mobile Video Wireless Delivery, Jianxin Sun

Department of Computer Electronics and Engineering: Dissertations, Theses, and Student Research

Micro-electronic industry has been boosting the capability of wireless mobile devices on full-scale. However, battery, as the only power source of most mobile devices, is experiencing a relatively slow development. Therefore, how to optimally utilize the limited battery energy on mobile devices under a predefined performance requirement becomes a critical issue. On the other hand, it is still unclear that how the battery capacity consumption is allocated on different working pattern of a specific video codec under various tempo-spatial scales and parameters, which has posed a design challenge on power management on multimedia communication system. Furthermore, an optimization method is …

An Enhanced Method To Measure Pulse Dispersion In Uwb Antennas, Antoine Dumoulin, Matthias John, Patrick Mcevoy, Max Ammann

Conference Papers

This paper will demonstrate a method to remove the dispersive effects of antennas and measurement equipment from a real time-domain measurement setup. By isolating the AUT transfer function, more accurate time-domain measurements can be achieved and agreement to simulation improved.

Vivaldi Array For Generation Of Uwb Circular Polarization, Adam Narbudowicz, Matthias John, Xiulong Bao, Max Ammann

Conference Papers

A two antenna array is proposed for generating circular polarization for an ultra-wideband system. It consists of two orthogonal antipodal vivaldi antennas and a feed network which provides the appropriate phase and amplitude over the band of interest. The proposed structure is low cost and easy to manufacture, offering an axial-ratio bandwidth of 74%.

Scalability Study Of Explicit Finite Element Method On Shared And Distributed Memory Architectures, Leonardo Orea-Amador, Jack F. Chessa Ph.D.

COURI Symposium Abstracts, Summer 2012

Parallel architectures in computer systems are powerful tools for processing enormous amounts of information. The results of this research will illustrate their optimal usage by evaluating the scalability of the code Abaqus in the cases of domain decomposition and loop parallelization architectures. The scalability was analyzed using concomitant variation having the DoF (Degrees of Freedom) and CPU (Central Processing Unit) numbers as the variables. Abaqus jobs with less than 100,000 DoF showed similar scalability than that of jobs with more than 500,000. These results contradict the original hypothesis which proposed that small jobs would show poor scalability and vice versa. …

Optimized Monopole And Dipole Antennas For Uwb Asset Tag Location Systems, Antoine Dumoulin, Matthias John, Max Ammann, Patrick Mcevoy

Articles

Miniaturized monopole and dipole antenna designs are reported with performances optimized for ultrawideband pulsed radio applications. The geometries are created using Bézier spline shapes, which have been refined with a genetic algorithm to simultaneously take account of both frequency- and time-domain criteria. Time-domain measurements of ultra wideband antennas with uniformly distributed energy across the full 3.1-10.6 GHz mask are reported for the first time and validate a new approach to minimization of pulse dispersion effects in the antenna designs.

802.15.4 Low Intermediate Frequency Radio Receiver, Sanjay Avasarala

Electrical Engineering

This project involves the design, building, and testing of a low intermediate frequency 802.15.4 receiver that uses an FPGA to perform final demodulation to baseband.

Pulsed Class-G Rf Amplifier System, Kevin Maulhardt, Kevin Haskett

Electrical Engineering

No abstract provided.

Adaptive Security-Aware Scheduling For Packet Switched Networks Using Real-Time Multi-Agent Systems, Ma'en Saleh Saleh

Dissertations

Conventional real-time scheduling algorithms are in care of timing constraints; they don’t pay any attention to enhance or optimize the real-time packet’s security performance. In this work, we propose an adaptive security-aware scheduling with congestion control mechanism for packet switching networks using real-time agentbased systems. The proposed system combines the functionality of real-time scheduling with the security service enhancement, where the real-time scheduling unit uses the differentiated-earliest-deadline-first (Diff-EDF) scheduler, while the security service enhancement scheme adopts a congestion control mechanism based on a resource estimation methodology.

The security service enhancement unit was designed based on two models: singlelayer and weighted …

Rfid Check-In System For Safe Routes To School At Hawthorne Elementary, Paul Banel

Electrical Engineering

The system uses a low frequency Radio Frequency Identification (RFID) reader and passive RFID tags to help the Safe Routes to School program at Hawthorne Elementary in San Luis Obispo track the number of children who participate in the program. Children will carry passive RFID tags and scan them at the reader each morning that they walk or bike to school. The system tracks the total number of students that walk and bike each day, as well as the number of times each individual child participates over the course of many days. The Safe Routes program hopes to use this …

Lyfi, Kianoosh Salami, Justin Cotton, Elush Shirazpour

Electrical Engineering

This paper will cover the steps necessary to design, build, and manage networkable smart light switches over WiFi via a mobile application. It contains a microcontroller running a real time operating system, a WiFi module, a Java server with SQLite databasing, and a mobile phone application.

LyFi is designed to turn on/off and dim household lights while only requiring the same installation procedure as a less capable dimmer switch. Once installed and connected to a network, LyFi will self-discover and configure. The server automatically propogates a database of nodes where any mobile device running an application can receive an updated …

Linear Power-Efficient Rf Amplifier With Partial Positive Feedback, Matthew E. King

Master's Theses

Over the last decade, the number of mobile wireless devices on the market has increased substantially. New “multi-carrier” modulation schemes, such as OFDM, WCDMA, and WiMAX, have been developed to accommodate the increasing number of wireless subscribers and the demand for faster data rates within the limited commercial frequency spectrum. These complex modulation schemes create signals with high peak-to-average power ratios (PAPR), exhibiting rapid changes in the signal magnitude. To accommodate these high-PAPR signals, RF power amplifiers in mobile devices must operate under backed-off gain conditions, resulting in poor power efficiency. Various efficiency-enhancement solutions have been realized for backed-off devices …