Digital Commons Network^™

A "Divide And Conquer" Technique For Implementing Wide Dynamic Range Continuous-Time Filters, Yorgos Palaskas, Yannis Tsividis, Vladimir I. Prodanov, Vito Boccuzzi

Electrical Engineering

This paper presents a technique for implementing analog filters with wide dynamic range and low power dissipation and chip area. The desired dynamic range of the filter is divided into subranges, each covered by a different filtering path optimized specifically for this subrange. This results in small admittance levels for the individual filtering paths and correspondingly small power dissipation and chip area. The system provides undisturbed output during range switching, contrary to conventional automatic gain control (AGC)/filter arrangements that generate disturbances every time the gain of the AGC changes. We also report on a low-noise highly linear CMOS transconductor useful …

Laboratory Project In Wireless Fsk Receiver Design, Michael A. Jensen, Cynthia Fuse, Raymond Woodward

Faculty Publications

This paper describes a wireless local area network laboratory project that provides senior and first-year graduate students in microwave engineering courses the opportunity to design, build, and test several passive microstrip components and integrate them into a working system. Students design filters, couplers, amplifiers, diode detectors, quarter-wave transformers, antennas, and stub matching networks in weekly labs that parallel-lectures in a one-semester microwave engineering course. This paper also describes simple inexpensive prototyping and testing methods that have been used in this course. Laboratory materials and technical details of the design are provided on the web for students and educators.

Wide-Band/Dual-Band Packaged Antenna For 5-6 Ghz Wlan Application, Mohammod Ali, Tuangsit Sittironnarit, Huan-Sheng Hwang, Robert A. Sadler, Gerard James Hayes

Faculty Publications

A wide-band/dual-band packaged antenna is proposed for wireless local-area network (WLAN) applications in the 5.15-5.35 GHz and 5.725-5.825 GHz frequency range. The antenna is internal to the housing of a personal digital assistant, such as a Palm organizer, and has the dimensions of 28 by 9 by 3 ram on an FR4 substrate. The antenna meets or exceeds the bandwidth requirements for the dual-band IEEE 802.11a WLAN applications (5.15-5.35 GHz and 5.725-5.825 GHz) within 2:1 voltage standing-wave ratio.

Common-Mode Current Due To A Trace Near A Pcb Edge And Its Suppression By A Guard Band, Yoshiki Kayano, Motoshi Tanaka, James L. Drewniak, Hiroshi Inoue

Electrical and Computer Engineering Faculty Research & Creative Works

The common-mode (CM) current due to a trace near a printed circuit board (PCB) edge, and its suppression by a guard band have been studied experimentally and with finite-difference time-domain (FDTD) modeling. As the guard band, copper tape is connected along the entire edge of the ground plane. First, a PCB electromagnetic interference (EMI) coupling path that results from the nonzero impedance of the PCB ground plane is discussed. As the trace is moved closer to the PCB edge, the CM current increases. Then, the effect of the guard band on the CM current is detailed. A guard band parallel …

A Multi-Processor Control System Architecture For A Cascaded Statcom With Energy Storage, Chang Qian, Stan Atcitty, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a multi-processor control system for a general purpose five-level cascaded inverter for real time power system applications. Practical design considerations for the digital controller architecture as well as the power converter are discussed and a 3 kVA laboratory prototype is presented. As a case study, a StatCom with battery energy storage was implemented on this multi-processor controlled inverter system. To eliminate the troublesome PI parameter tuning and the limitation of small signal models, which exist in conventional control for StatComs, a new and simple control method based on large signal model was designed to realize four-quadrant power …

A Reconfigurable Facts System For University Laboratories, Liangying Dong, Zhiping Yang, Shen Chen, Lin Zhang, Stan Atcitty, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

To fully understand the dynamic performance of the multiple flexible ac transmission systems (FACTS) devices, a hardware setup is needed to complement software simulation for university research laboratories. This paper presents the schematic and basic controls of a reconfigurable FACTS system that can be used to realize the major voltage-sourced-converter FACTS topologies: the StatCom, the static synchronous series compensator (SSSC), and the unified power-flow controller (UPFC). Furthermore, the state models and control algorithms for the FACTS devices are proposed. The digital signal processor (DSP)-based control system enables new control methods to be rapidly implemented. The comparison of the experimental and …

Pulse Regulation Control Technique For Flyback Converter, Mehdi Ferdowsi, Ali Emadi

Electrical and Computer Engineering Faculty Research & Creative Works

Pulse regulation, a fixed frequency control technique, is introduced and applied to flyback converter operating in discontinuous conduction mode (DCM). The control parameters are designed in a way that the converter operates as close as possible to the critical conduction mode. In contrast to the conventional pulse width modulation (PWM) control scheme, the principal idea of pulse regulation is to achieve output voltage regulation using high and low-power pulses. Pulse regulation is simple, cost effective, and enjoys a fast dynamic response. The proposed technique is applicable to any converter operating in DCM. However, this work mainly focuses on flyback topology. …

An Efficient Multirate Simulation Technique For Power-Electronic-Based Systems, Steven D. Pekarek, Oleg Wasynczuk, Eric A. Walters, Juri V. Jatskevich, Charles E. Lucas, Ning Wu, Peter T. Lamm

Electrical and Computer Engineering Faculty Research & Creative Works

A novel multirate method of simulating power-electronic-Based systems containing a wide range of time scales is presented. in this method, any suitable integration algorithm, with fixed or variable time-step, can be applied to the fast and/or slow subsystems. the subsystems exchange coupling variables at a communication interval that can be fixed or varied dynamically depending upon the state of the system variables. the proposed multirate method is applied to two example power systems that include power-electronic subsystems. Increases in simulation speed of 183-281% over established single-rate integration algorithms are demonstrated.

Oblivious Data Hiding : A Practical Approach, Husrev T. Sencar

Dissertations

This dissertation presents an in-depth study of oblivious data hiding with the emphasis on quantization based schemes. Three main issues are specifically addressed:

1. Theoretical and practical aspects of embedder-detector design.

2. Performance evaluation, and analysis of performance vs. complexity tradeoffs.

3. Some application specific implementations.

A communications framework based on channel adaptive encoding and channel independent decoding is proposed and interpreted in terms of oblivious data hiding problem. The duality between the suggested encoding-decoding scheme and practical embedding-detection schemes are examined. With this perspective, a formal treatment of the "processing" employed in quantization based hiding methods is presented. In …

Ip-Based Virtual Private Networks And Proportional Quality Of Service Differentiation, Jingdi Zeng

Dissertations

IP-based virtual private networks (VPNs) have the potential of delivering cost-effective, secure, and private network-like services. Having surveyed current enabling techniques, an overall picture of IP VPN implementations is presented.

In order to provision the equivalent quality of service (QoS) of legacy connection-oriented layer 2 VPNs (e.g., Frame Relay and ATM), IP VPNs have to overcome the intrinsically best effort characteristics of the Internet. Subsequently, a hierarchical QoS guarantee framework for IP VPNs is proposed, stitching together development progresses from recent research and engineering work.

To differentiate IP VPN QoS, the proportional QoS differentiation model, whose QoS specification granularity compromises …

Configurable Computer Systems Can Support Dataflow Computing, Anish Arvind Sathe

Theses

This work presents a practical implementation of a uni-processor system design. This design, named D²-CPU, satisfies the pure data-driven paradigm, which is a radical alternative to the conventional von Neumann paradigm and exploits the instruction-level parallelism to its full extent. The D²-CPU uses the natural flow of the program, dataflow, by minimizing redundant instructions like fetch, store, and write back. This leads to a design with the better performance, lower power consumption and efficient use of the on-chip resources. This extraordinary performance is the result of a simple, pipelined and superscalar architecture with a very …

Studies In Multiple-Antenna Wireless Communications, Christian Bruce Peel

Theses and Dissertations

Wireless communications systems are used today in a variety of milieux, with a recurring theme: users and applications regularly require higher throughput. Multiple antennas enable higher throughput and/or more robust performance than single-antenna communications, with no increase in power or frequency bandwidth. Systems are required which achieve the full potential of this "space-time" communication channel under the significant challenges of time-varying fading, multiple users, and the choice of appropriate coding schemes. This dissertation is focused on solutions to these problems. For the single-user case, there are many well-known coding techniques available; in the first part of this dissertation, the performance …

A Faster Technique For Distributed Constraint Satisfaction And Optimization With Privacy Enforcement, Marius C. Silaghi

Electrical Engineering and Computer Science Faculty Publications

A problem that received recent attention is the development of negotiation/cooperation techniques for solving naturally distributed problems with privacy requirements. An important amount of research focused on those problems that can be modeled with distributed constraint satisfaction, where the constraints are the secrets of the participants. Distributed AI develops techniques where the agents solve such problems without involving trusted servers. Some of the existing techniques aim for various tradeoffs between complexity and privacy guarantees [MTSY03], some aim only at high efficiency [ZM04], while others aim to offer maximal privacy [Sil03]. While the last mentioned work achieves an important level of …

Effective Quality Analysis For Video Streaming Over Wireless Ad Hoc Network, Zhihai He, Chang Wen Chen

Electrical Engineering and Computer Science Faculty Publications

Video encoding and streaming over wireless ad hoc network operates under severe conditions, such as time-varying channel characteristics with bursty errors, limit power for data transmission, and dynamic topology of the self-organized network, stringent time delay for packet delivery, etc. Due to the dynamic topology, complex mechanism, and time-varying nature of the wireless ad hoc network, the network system and the streaming service often exhibit unpredictable behaviors. The ultimate goal in the wireless video streaming service is to provide the end user with the best possible video presentation quality. The video streaming quality, often measured by the end-to-end picture distortion, …

Collaborative Image Transmission Over Wireless Sensor Networks, Min Wu, Chang Wen Chen

Electrical Engineering and Computer Science Faculty Publications

The imaging sensors are able to provide intuitive visual information for quick recognition and decision. However, imaging sensors usually generate vast amount of data. Thus, processing of image data collected in the sensor network for the purpose of energy efficient transmission poses a significant technical challenge. In particular, when a cluster of imaging sensors is activated to track certain moving target, multiple sensors may be collecting similar visual information simultaneously. With correlated image data, we need to intelligently reduce the redundancy among the neighboring sensors so as to minimize the energy for transmission, the primary source of sensor energy consumption. …

A Half D1 Mpeg-4 Encoder On The Bsp-15 Dsp, Lulin Chen, Zhihai He, Chang Wen Chen, Michael A. Isnardi

Electrical Engineering and Computer Science Faculty Publications

In this paper, we present the work on implementation of a half-Dl interlaced MPEG-4 encoder with Equator Technology DSP chip, BSP-15. The BSP-15 DSP consists mainly of a VLIW core, Co-processors, and media I/O interfaces. The encoder utilizes several BSP-15 functional blocks in parallel. In general, the VLIW performs pixel processing that is computationally intensive. The VLx coprocessor completes variable length coding. Further parallelism is obtained by pre-loading data cache and doubling data buffers. Given the DSP processing power and real time requirements, a complexity control scheme is implemented. A frame-level quantization scheme with quality and rate control is employed. …

Layered Unequal Loss Protection For Progressive Image Transmission Over Packet Loss Channels, Jianfei Cai, Xiangjun Li, Chang Wen Chen

Electrical Engineering and Computer Science Faculty Publications

In the past, many schemes have been proposed for progressive image transmission using unequal error protection (UEP) or unequal loss protection (ULP). However, most existing UEP/ULP schemes do not consider the minimum image quality requirement and usually have high computation complexity. In this paper, we propose a layered ULP (L-ULP) scheme for progressive image transmission over packet loss channels, which is able to solve the mentioned problems of existing ULP schemes by smartly choosing the layers. The numerical results show that the proposed L-ULP scheme is quite promising for fast image transmission over packet loss networks.

Optically Coupled Etalons And Methods Of Making And Using Same, Michael A. Scobey, Lucien P. Ghislain, Dennis Derickson, Loren F. Stokes

Electrical Engineering

Optical elements comprise stacked, optically matched and optically coupled etalons, at least one of the optically coupled etalons comprising first and second selectively transparent thin film mirror coatings on opposite surfaces of a bulk optic. The bulk optic defines the cavity spacing of the etalon and may, for example be formed of a monolithic body of silica or other optically transparent glass diced from a glass wafer. The bulk optic may further comprise a wedge coating of progressively increasing thickness overlying the monolithic glass body and compensating for, or offsetting non-parallelism of the bulk optic. The bulk optic may further …

Characterization Of Ingan/Gan Multi-Quantum-Well Blue-Light-Emitting Diodes Grown By Metal Organic Chemical Vapor Deposition, K. S. Ramaiah, Y. K. Su, S. J. Cheng, B. Kerr, H. P. Liu, I. G. Chen

Electrical and Computer Engineering Publications

The structural,surface morphology, and the temperature dependence photoluminescence of InGaN(3 nm)/GaN(7 nm) 5 period multi-quantum-well blue-light-emitting diode (LED)structures grown by metal organic chemical vapor deposition(MOCVD) have been studied. Quantum dot-likestructures and strain contrast evident by black lumps were observed in the quantum wells using high-resolution transmission electron microscopy(HRTEM) analysis. Double-crystal high-resolution x-ray diffraction (HRXRD) spectra of blue LED were simulated using kinematical theory method, to obtain composition, and period thickness of well and barrier. The “S” shape character shift as red–blue–redshift of the quantum-well emission line, i.e., blue emission peak 2.667 eV at 10 K, was observed with variation of …

Balancedenergy Sleep Scheduling Scheme For High Density Cluster-Based Sensor Networks, Jing Deng, Yunghsiang S. Han, Wendi B. Heinzelman, Pramod K. Varshney

Electrical Engineering and Computer Science - All Scholarship

In order to conserve battery power in very dense sensor networks, some sensor nodes may be put into the sleep state while other sensor nodes remain active for the sensing and communication tasks. However, determining which of the sensor nodes should be put into the sleep state is non-trivial. As the goal of allowing nodes to sleep is to extend network lifetime, we propose and analyze a Balanced-energy Scheduling (BS) scheme in the context of cluster-based sensor networks. The BS scheme aims to evenly distribute the energy load of the sensing and communication tasks among all the nodes in the …

Printed Planar Monopole Antenna With Electromagnetically Coupled Elements, Jonathan Evans, Francisco Lerma, Max Ammann

Conference papers

In this paper, the addition of an EM-coupled element to the printed planar monopole antenna is investigated. While remaining simple to construct, modifications to the EM-coupled element are shown to reduce the lower edge frequency of the 10 dB impedance bandwidth by up to ∼19% (280 MHz at 1.5 GHz). The radiation patterns for these antennas are characteristic of monopole antennas - i.e. omnidirectional in the azimuth plane with a at the zenith - and are consistent within +/- 2 dB across their useful impedance bandwidths. By optimizing the feed arrangements on these antennas a 10 dB impedance bandwidth ratio …

The Values Of Being Small And Nimble, Joshua Shuart, Peter Christian ("Chris") Murphy

New England Journal of Entrepreneurship

Peter Christian (Chris) Murphy had worked his way up the “food chain” at AT&T for 19 years, culminating in his position as Sales Center Vice President for South Florida. When he and a coworker realized there was an opportunity in the marketplace for a small, nimble company to take advantage of emerging communications technology that a stodgy, lumbering corporation would have trouble integrating into its service package, Chris decided to jump into an entrepreneurial opportunity.

The Removal Of Motion Artifacts From Non-Invasive Blood Pressure Measurements, Paresh Thakkar

Electronic Theses and Dissertations

Modern Automatic Blood Pressure Measurement Techniques are based on measuring the cuff pressure and on sensing the pulsatile amplitude variations. These measurements are very sensitive to motion of the patient or the surroundings where the patient is. The slightest unexpected movements could offset the readings of the automatic Blood Pressure meter by a large amount or render the readings totally meaningless. Every effort must be taken to avoid subjecting the body of the patient or the patient's surroundings to motion for obtaining a reliable reading. But there are situations in which we need Blood Pressure Measurements with the patient or …

Observations Upon Entering The Kettle, Gary Spivey

Faculty Publications - Department of Electrical Engineering and Computer Science

An oft told parable relates how a frog, when dropped in a kettle of hot water, will instantly jump out. But if you drop that frog in a kettle of cold water, and slowly heat it up, the frog will not be aware of the gradual change in its environment and will die in the kettle. I had formerly limited the kettle analogy to the broad concepts of the “worldly culture” alluded to by pastors who use this imagery. Then, after completing educational experience at major state universities and a fifteen year career in industry, I decided to enter upon …

An Asynchronous Gals Interface With Applications, Jennifer A. Smith

Electrical and Computer Engineering Faculty Publications and Presentations

A low-latency asynchronous interface for use in globally-asynchronous locally-synchronous (GALS) integrated circuits is presented. The interface is compact and does not alter the local clocks of the interfaced local clock domains in any way (unlike many existing GALS interfaces). Two applications of the interface to GALS systems are shown. The first is a single-chip shared-memory multiprocessor for generic supercomputing use. The second is an application-specific coprocessor for hardware acceleration of the Smith-Waterman algorithm. This is a bioinformatics algorithm used for sequence alignment (similarity searching) between DNA or amino acid (protein) sequences and sequence databases such as the recently completed human …

Using Information Technology To Enhance Control Engineering Education: Some Experiences, Aidan O'Dwyer

Conference papers

In the past decade, the use of computer based design and analysis tools, such as MATLAB/SIMULINK, has revolutionised practice in Control Engineering. Concepts that were previously only understandable after sustained mathematical analysis or experimental work may now be readily simulated on the computer. Over the past four years, the author has experimented with the use of MATLAB/SIMULINK, in the lecture and laboratory environment, with degree and taught masters students in control engineering at Dublin Institute of Technology (DIT). It has been found that the tool helps to increase student understanding of challenging topics, to act as motivation to further exploration …

Harmonic Distortion Caused By Ev Battery Chargers In The Distribution Systems Network And Its Remedy, Malabika Basu, Kevin Gaughan, Eugene Coyle

Conference papers

An effective way to minimise harmonic pollution in power systems is by careful design of the equipment connected to them. It is important for designers of equipment associated with emerging technologies to be aware of the potential impact of their designs on power system quality. One such upcoming technology is electric vehicle (EV) battery charging which may contribute to high harmonic distortion in the power system during the charging period. The literature notes total harmonic distortion of up to 50%. These findings are the impetus behind the present paper, where an EV battery charger has been designed, with an inherent …

Enhancing Process Performance Through Automatic Control, Aidan O'Dwyer

Conference papers

The proportional integral derivative (PID) controller is the most dominant form of automatic controller in industrial use today. With this technique, it is necessary to adjust the controller parameters according to the nature of the process. Thus, for effective control of a pasteurisation process, for example, specific values need to be chosen for the P, I and D parameters, which will be different for the values required to control, for example, a distillation column. This tailoring of controller to process is known as controller tuning.

Energy Aware Design And Analysis For Synchronous And Asynchronous Circuits, Jia Di

Retrospective Theses and Dissertations

Power dissipation has become a major concern for IC designers. Various low power design techniques have been developed for synchronous circuits. Asynchronous circuits, however. have gained more interests recently due to their benefits in lower noise, easy timing control, etc. But few publications on energy reduction techniques for asynchronous logic are available.

Power awareness indicates the ability of the system power to scale with changing conditions and quality requirements. Scalability is an important figure-of-merit since it allows the end user to implement operational policy. just like the user of mobile multimedia equipment needs to select between better quality and longer …

Modified Sierpinski Fractal Antenna, Tripti Luintel

Electronic Theses and Dissertations

Fractal antennas have the potential to provide multi-band solution through the property of self similarity that the fractal shape possess. This thesis deals with some modifications of the original Sierpinski fractal patch antenna, providing additional parameters to optimize in order to get the required radiation characteristics. A systematic study of the original Sierpinski monopole was done to gain an insight on the operation and multi-band behavior of the antenna and a similar study was done to find out why the patch version of Sierpinski lacks multi-band behavior. A Sierpinski antenna is designed by merging a grid and the fractal restoring …