Scheduled System Maintenance:
On Monday, April 27th, IEEE Xplore will undergo scheduled maintenance from 1:00 PM - 3:00 PM ET (17:00 - 19:00 UTC). No interruption in service is anticipated.
By Topic

Date 5-7 April 2002

Filter Results

Displaying Results 1 - 25 of 95
  • Proceedings IEEE SoutheastCon 2002 (Cat. No.02CH37283)

    Publication Year: 2002
    Save to Project icon | Request Permissions | PDF file iconPDF (355 KB)  
    Freely Available from IEEE
  • Author index

    Publication Year: 2002 , Page(s): 481 - 482
    Save to Project icon | Request Permissions | PDF file iconPDF (83 KB)  
    Freely Available from IEEE
  • A resource synchronization protocol for dynamic scheduling real-time CORBA

    Publication Year: 2002 , Page(s): 15 - 20
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (530 KB)  

    In 1989, the Object Management Group (OMG) formed a Real-Time Special Interest Group (RT SIG) with the goal of extending the Common Object Request Broker Architecture (CORBA) standard with real-time specifications. The most recent effort attempts to meet the requirements of dynamic distributed real-time systems. In such systems, one of the requirements is resource access synchronization for tasks with end-to-end timing constraints under dynamic scheduling. The paper proposes a resource synchronization protocol that meets the requirements of the dynamic distributed realtime system specified by the Dynamic Scheduling Real-Time CORBA (DSRT CORBA). The proposed protocol can be applied to both Earliest Deadline First (EDF) and Least Laxity First (LLF) dynamic scheduling algorithms, allows distributed nested critical sections, and avoids unnecessary runtime overhead View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The practical use of model checking in software development

    Publication Year: 2002 , Page(s): 21 - 27
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (597 KB)  

    The paper presents the result of work that explored the use of model checking, investigated modeling tools, and developed a process for model checking software systems. A prototype tool for visual modeling was developed and helped the research team understand the role of tools, such as SMV, and clarified the steps involved in the model checking process. The paper summarizes the engineering observations made by team members during their model checking work. These observations were refined through the use of simple challenge problems and organized into a process that highlights some of the practical issues associated with model checking software systems View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Accessing devices using a Web service

    Publication Year: 2002 , Page(s): 463 - 467
    Cited by:  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (374 KB)  

    The time when embedded devices and factory-floor machines had only minimal interaction with humans is gone. Today, the ability to access a device from anywhere is expected. This is a significant challenge when we are heavily constrained by hardware size and costs. However, with commonly available software components and a little knowledge, we can incorporate a "universal" access interface for data gathering/surveillance that maintains a small footprint and that is secure View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Advancing technology in wireless communications

    Publication Year: 2002 , Page(s): 468 - 470
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (323 KB)  

    This paper presents information on the recent advances of practical wireless networks for voice, data, image and video services in areas as small as an office and as large as the entire planet. This paper also addresses the potential economic and sociological impacts of mobile communications. We also discuss the next generation of cellular telephones, computer networks and pagers being developed to meet the demands of increased quality and capacity of a growing telecommunication market View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Integratable robot simulation tools

    Publication Year: 2002 , Page(s): 370 - 374
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (453 KB)  

    A new graphical simulation package, which is capable of interoperability with other extensive programs, is proposed. A built-in LISP interpreter based on COMMON LISP allows a user to model and manipulate the robot while the result is displayed on a 3D graphical display. Other programming languages that are compatible with the component object model interface can also be applied to the modeling and simulation. The simulation package provides many useful features such as collision detection, inverse kinematics, matrix transformation operations, and several graphical user interfaces. The simulation objects are built based on a triangle strip model to form primitive objects such as a box, cone, sphere, etc. These primitive objects are combined to construct the robot that may contain several serial or parallel links so that many possible types of robots can be modeled View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • TSNU-PSTD modeling of a simplified indoor wave propagation for wireless network communications

    Publication Year: 2002 , Page(s): 205 - 209
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (358 KB)  

    In this research, we develop a transformed-space, nonuniform pseudo-spectral time domain (TSNU-PSTD) Maxwell solver for modeling a simplified indoor wave propagation in a multilayer dielectric system for wireless local area network (WLAN) communications. Herein, we transform a nonuniform grid {xi} to a uniform one {ui} to fit for dimensions of practical structures prior to applying the standard fast Fourier transform (FFT). It is reported that this scheme is as efficient as the conventional uniform PSTD with a computational complexity of O(NlogN) since the difference is only the factor of du/dx between the conventional PSTD and the TSNU-PSTD techniques. An initial-condition excitation of a Gaussian pulse over the entire computational domain is employed as the initial excitation to eliminate undesired Gibbs phenomena, which could seriously deteriorate the implementation of the PSTD. An anisotropic version of the Berenger perfectly matched layers (APML) is used to suppress the wraparound effect at the two ends of the computational domain, which is caused by the periodicity of the FFT View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Advantages of slowed electromagnetic waves

    Publication Year: 2002 , Page(s): 375 - 380
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (507 KB)  

    The features of slowed electromagnetic waves and their advantages are considered. Examples of new methods and devices combining the advantages of relatively high and relatively low frequency bands are shown. Concentration of an electromagnetic field caused by wave deceleration leads to a significant increase in parameters of processes and devices based on slowed wave application. It is shown that coupled slow-wave structures application allows electric and magnetic fields to split in transverse direction which leads to an additional improving in parameters and characteristics (the sensitivity and interaction efficiency increase, new processes developing, etc.). The possibilities of slowed wave application for micro-miniaturization of RF and microwave passive elements, for measurements, electromagnetic heating, and for physiotherapy are considered View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Combined acoustic target tracking and sensor localization

    Publication Year: 2002 , Page(s): 437 - 440
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (326 KB)  

    This study investigates the application of a batch oriented maximum a posteriori (MAP) estimation scheme to the problem of tracking a moving target using acoustic bearing-only data from sensors with unknown positions. In this paper a simple method for determining sensor location and movement from the measured acoustic data is proposed, and is subsequently utilized to update the sensor positions to reduce tracking errors. The Cramer-Rao bound (CRB) on the estimate is derived, and simulations show that the proposed method compares favorably to the bound View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Extended BOR-FDTD algorithm for the analysis of cylindrical guided-wave structures and antennas

    Publication Year: 2002 , Page(s): 210 - 214
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (368 KB)  

    In this research, a cylindrical, nonuniform finite difference time domain technique is developed for solving Maxwell's equations with body of revolution (BOR) geometries. The rotational symmetry of structures enables us to employ a two-dimensional (2D) finite difference lattice in the field timestepping procedure by projecting a three-dimensional (3D) Yee cell in cylindrical coordinates (r, φ, z) onto the (ρ, z) plane. The perfectly electric conductor (PEC) or the anisotropic perfectly matched layer (APML) is used to truncate the computational domain in the ρ and z-axes. Extensive numerical results have been derived for various cylindrical guided-wave structures and horn antennas, and these results have been compared with those available in the literature. Excellent agreement and great efficiency have been observed for all of the cases investigated in this research View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Multiple path planning for a group of mobile robots in a 3D environment using genetic algorithms

    Publication Year: 2002 , Page(s): 359 - 363
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (391 KB)  

    We present the development, simulation and testing of a new approach using genetic algorithms for planning optimum paths for a group of mobile robots to be moved from arbitrary starting positions to final a number of targets in a known multi-obstacle 3D environment. The factors considered for fording optimum paths for the group of mobile robots are the size and location of obstacles in the environment and the topographical elevations of the environment. First, a digital picture of the environment is transformed into a grid map by a graphic simulator. The obstacles are mapped according to their location, shape and size. The ground elevations are represented using a color-coding scheme. The resulting grid map of the environment contains information about initial positions of the robots, target positions, obstacle locations and ground elevation. Hence, the location and size of obstacles and altitudes of the elevation of the environment are presented in the map. The genetic algorithm modules takes information about the environment from the grid map and search for optimum paths to move a group of mobile robots to the specified targets View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Design and development of a user interface to remotely control a radio telescope using virtual instruments

    Publication Year: 2002 , Page(s): 279 - 282
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (357 KB)  

    Radio telescopes are the main instruments used in radio astronomy. In order to encourage students of Grades K-12 to be interested in astronomy, a group of students from South Carolina State University have undertaken to computerize a 4.6 meter telescope, called Smiley. The team of students proposed to use a graphical programming language, called Laboratory Virtual Instruments Engineering Workbench (abbreviated LabVIEW) for instrumentation, data acquisition and analysis View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Baseband system design for a multi-mode 802.11 a/b wireless LAN adapter

    Publication Year: 2002 , Page(s): 322 - 325
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (311 KB)  

    Multi-mode, programmable wireless LAN systems could have important benefits for manufacturers and consumers. They are initially slightly more complicated than a single-mode, fixed function system to design, but allow better data throughput, better coverage, and fast time-to-market for upgrades. The system model for an IEEE 802.11a/b wireless LAN system-on-a-chip is described. Programmable solutions for the MAC and PHY baseband layers are identified and contrasted with fixed function solutions. Detailed design issues of re-use of hardware and revision of software functional blocks in the PHY to provide both coverage and cost benefits are evaluated View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Mapping the effect of a circuit impedance on the common-mode excitation of electromagnetic interference

    Publication Year: 2002 , Page(s): 104 - 107
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (314 KB)  

    The control of electromagnetic radiation from electronic products in order to comply with the various governmental standards regulating electromagnetic interference around the world is a challenging part of the product design process. A principal reason is the relative difficulty of accurately modeling the way the common-mode portion of the radiation is produced. In Jerse (1999) a common-mode impedance measured at the driving point of a circuit was derived along with a numerical method to compute it. This impedance can be used as a single figure-of-merit to assess the proclivity of a configuration to generate common-mode emissions. As a result, design tradeoffs can be made without performing extensive full-wave analyses and decomposing the derived currents into their modal components. The work described in this paper extends the technique to permit the inclusion of a variable external circuit element and takes advantage of this single figure-of-merit to gauge the effect of the impedance of a transmission line load on the common-mode excitation of an example circuit View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Development of software for mobile robot control over a radio frequency communications link

    Publication Year: 2002 , Page(s): 414 - 417
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (360 KB)  

    In the spring of 2001, work began on a mobile robot for an advanced computer engineering class. One of the key parts to the success of this robot would be the ability to control it from a computer terminal. In order to make this feasible, the computer would communicate to the robot through a wireless connection. The robot's on-board computer would perform any computations needed, so the robot would not need to send any information on the controlling computer. The communication link was designated to be one way, from the computer to the robot. For reasons including cost efficiency, ease of use, and range, RF communication was chosen. Using two development boards from Linx Technologies, we had the capability of communicating through the computer's serial port. The boards boasted a line of sight range of about 1000 feet. The board acts as nothing more then a transmitter and receiver, so any error correction must be dealt with in the software. Often errors come from interference created by surrounding RF devices, and appear as incorrect bits in the data stream. In order to handle such errors, methods involving redundancy were used. When the stream of information is sent, it is initialized by a start byte. This is followed by the commands, each of which is repeated three times followed by a stop byte. On the receiving end, the software waits for the start byte and then stores each byte that follows. They are then compared with one another and determined to be either clean data or an error. If the data is clean, the robot then executes the commands. By monitoring the data received by the receiver we were able to see the need for such software. Upon powering up the board, miscellaneous bits are received, and if there is no error correction, the robot could misinterpret these for a command. The boards also received stray bytes while idle, so the software would also eliminate this. Software development was started and initially tested over a crossover cable connecting the two serial ports. This allowed us to ensure that the software was working with out seeing any errors at first. Finally the software was used with the RF boards and seen to be functional. This paper explores, in depth, the methods used by software to correct errors that may develop in RF communication. The materials used are discussed in greater detail along with the creation of the software. Experimental results show the methods to be precise, and fit the design application needs View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Application of a 2D-CFDTD algorithm to the analysis of photonic crystal fibers (PCFs)

    Publication Year: 2002 , Page(s): 215 - 219
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (342 KB)  

    In this research, we apply an efficient two-dimensional cylindrical finite difference time domain (2D-CFDTD) algorithm to analyze a photonic crystal fiber (PCF) structure. An unsplit anisotropic perfectly matched layer (APML) is used for mesh termination along the radial direction of the photonic crystal fiber (PCF). The propagation characteristics of PCF are analyzed and excellent agreement is observed between the results derived in this research and those available in the literature View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Stochastic/dynamic communication in a general Euniversal link

    Publication Year: 2002 , Page(s): 475 - 478
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (450 KB)  

    This paper compares known long and short code sequence generation techniques with the proposed arbitrary multidimensional code pattern synthesis and super high resolved code beams generation methods to obtain amplitude dependent performance function (rather than minimize SNR dependent exponential Pe). Furthermore, this paper compares spread-spectrum shaping techniques with the proposed no-sidelobe spectrum synthesis to obtain impulse correlation or multidimensional spectrum synthesis. This paper also explores the possibility of unifying an arbitrary code spectrum generation technique with arbitrary no-sidelobe spread-spectrum synthesis. Various molecular structures are also summarized in this paper to synthesize molecules with connections among its complex multidimensional components as atoms and sub-components. These maps are useful in material synthesis for super high speed communication, body sound propagation etc., and are applicable in the synthesis of chemical chain reactions and neural networks View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • 2-D auditory mapping of virtual environment using real-time head related transfer functions

    Publication Year: 2002 , Page(s): 364 - 369
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (554 KB)  

    The human brain is capable of localizing sounds from events occurring in its surroundings. It is able to identify and pinpoint from which directions the sounds come. This project takes advantage of that ability to create a simple auditory map of a virtual environment with the use of head related transfer functions (HRTF). HRTF are the basis of the most prominent techniques for digital sound spatialization. In this project a synthetic virtual environment is defined by a maze of vertical and horizontal walls drawn on the computer screen using Matlab's graphic user interface (GUI) components. In this virtual environment the subject is represented by the computer cursor. The distances from the cursor to the nearest virtual walls are calculated continuously and used to control the intensity of four virtual sounds that are simulated as if originating at the front, back, left and right of the subject. These four spatialized sounds are delivered through headphones to a blindfolded user as he/she navigates the virtual environment stepping the cursor with the four arrow keys on the keypad of the computer. Virtual navigation tests with 14 subjects confirm that the remote navigation cues provided by the spatialized sounds are more helpful in avoiding collisions with the virtual walls than a simple warning tone provided to the blindfolded user in the immediate vicinity of the walls View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Closed-loop position control system using LabVIEW

    Publication Year: 2002 , Page(s): 283 - 286
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (319 KB)  

    A closed-loop DC motor control system is developed using National Instrument's (NI) data acquisition (DAQ) board (Model MIO 6040E), LabVIEW software package, and DAQ signal accessory board for smooth and accurate positioning. The motor can be rotated either clockwise (CW) or counterclockwise (CCW) as needed. A linear feedback that employs a potentiometer provides the current position of the motor. The LabVIEW software is used to develop a virtual instrument (VI) that includes a front panel and a functional diagram. The VI reads the desired position of the motor entered by the user on the front panel and the current motor position via feedback, and determines its amount and direction of rotation. A smooth cubic polynomial that is continuous and has a continuous first and second derivative is utilized to represent the angular position of the motor. The VI uses the polynomial to generate a velocity profile which in turn is converted into a voltage profile for the motor armature through a conversion formula. This conversion formula is determined through the use of motor speed-voltage characteristics obtained from laboratory experiments. Reading the motor position and sending voltage to the motor circuit are accomplished via the DAQ's input and output ports respectively. The system is tested in the laboratory for different angular displacements and initial positions of the motor. Initial results are found to be satisfactory. This initiative is a preliminary work towards the development of a control system of one of the Radio Telescopes (called Smiley) at Pisgah Astronomical Research Institute (PARI) in Rosman, North Carolina View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Secure multimedia activity with redundant schemes

    Publication Year: 2002 , Page(s): 333 - 337
    Cited by:  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (419 KB)  

    The authors have investigated secure multimedia information transfers and maintained a redundant scheme in order to validate the information being exchanged. Also the migration from the MPEG2 standard to the MPEG4 (MPEG: Motion Picture Expert Group) plays an important role in the bandwidth utilization and security. These issues are taken into consideration during the investigations, in addition to the TCP/IP issues for multimedia transfers. In-building wireless links provide a cost effective means of linking systems, especially if the client systems have to be relocated often. The authors have addressed this issue and conducted investigations in terms of the reliability and throughput between systems with wireless links for multimedia file transfers. In this article, the authors present the multimedia architecture they have developed and the associated results of the information transfers in terms of the reliability and the throughput View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Design and implementation of a robot power supply system

    Publication Year: 2002 , Page(s): 418 - 421
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (318 KB)  

    Mobile robots often rely on a battery system as their main source of power. These systems typically produce a single voltage level, yet the robot subsystems may require a variety of voltage levels. Thus, a robot power supply must be designed to provide the subsystems with all of the necessary voltage and power demands. Student design work has progressed on a multifunctional robot project at Elizabethtown College. Current work has been focused on the design and fabrication of the robot power supply system. Since the main power source for the robot is a DC battery system, the power supply will consist of a combination of switched mode DC power converters. Choosing from the wide variety of existing DC converter topologies requires proper design consideration for the system voltage levels, component voltage ripple requirements, and overall converter efficiency. The main DC battery system also powers the drive motors, thus, voltage isolation and filtering is desirable for the robot's computer subsystems. A flyback converter topology is utilized to supply voltage isolation and regulation while subsequent buck converters are used to meet the remaining voltage requirements. This paper provides design and fabrication details on the buck converters used in the power supply system. The design meets the present robot subsystem requirements and allows for future project expansion, while the converter's efficiency maximizes the overall operating time for the robot. Experimental results show the converter efficiency and voltage ripple at rated load. A discussion of lessons learned provides insight into the need for proper component selection and placement, printed circuit board fabrication, and ensuring a proper ground plane for successful implementation of a switched mode DC power converter View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Wireless modem synchronization using an external reference

    Publication Year: 2002 , Page(s): 326 - 332
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (517 KB)  

    This paper discusses a communications system design for wireless modems incorporating an external reference for carrier synchronization. Motivation and a performance analysis in the presence of noise are given. Simulation results and initial field trial experiences are presented View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Implementation of the Silicon Track Card (STC) as a system-on-a-programmable-chip (SOPC)

    Publication Year: 2002 , Page(s): 108 - 112
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (404 KB)  

    The current paper details implementation of the Silicon Track Card (STC) card using a programmable logic device (PLD) for the DZERO (D0) upgrade currently underway at Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois. This project is a collaboration between researchers from the Department of Electrical and Computer Engineering, Florida Agricultural and Mechanical University-Florida State University (FAMU-FSU) College of Engineering, researchers from High Energy Physics (HEP), Florida State University and High Energy Physics, Boston University (BU). The STC project is based on the specifications provided by the researchers at BU and a preliminary STC module designed using the Very High Speed Integrated Circuit (VHSIC) hardware description language (VHDL). The upgraded STC has a modified memory map and a new Level 3 (L3) buffer module. Traditionally discrete components of memory and processor cores were externally connected, while current implementation aims at configuring them into a single device, thus increasing general system performance by decreasing board area and time delays associated with transmission lines on the printed circuit board. The STC targets the Advanced Programmable Embedded MatriX (APEX) family of PLDs developed by Altera Corporation View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The Paraguin compiler - message-passing code generation using SUIF [Stanford University Intermediate Format]

    Publication Year: 2002 , Page(s): 1 - 6
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (443 KB)  

    Introduces the Paraguin project at the University of North Carolina at Wilmington. The goal of the project is to build an open-source message-passing parallelizing compiler for distributed-memory computer systems. We discuss the progress we have made in developing this compiler as well as mention the parts that have not yet been developed. It is our intent that, by providing an open-source compiler, we will stimulate research in automatic message-passing parallelism and encourage collaboration. We demonstrate a technique to improve the performance of a message-passing program by overlapping communication with computation. Although the original concept was introduced previously by S.P. Amarasinghe and M.S. Lam (1993), the algorithm was not developed nor shown to provide any benefit. Our preliminary results indicate that the technique significantly improves the performance. We were able to reduce the running time of our test program by 4-65% View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.