University of Notre Dame

Displaying 1-40 of 235 results

  • White Papers // Mar 2012

    Fine-Grained Access Control in the Chirp Distributed File System

    Although the distributed file-system is a widely used technology in local area networks, it has seen less use on the wide area networks that connect clusters, clouds, and grids. One reason for this is access control: existing file-system technologies require either the client machine to be fully trusted, or the...

    Provided By University of Notre Dame

  • White Papers // Mar 2012

    Applying DDDAS Principles to Command, Control and Mission Planning for UAV Swarms

    Government agencies predict ever-increasing inventories of Unmanned Aerial Vehicles (UAVs). Sizes will vary from current manned aircraft scales to miniature, micro, millimeter scales or smaller. Missions for UAVs will increase, especially for the 3-D missions: dull, dirty, and dangerous. As their numbers and missions increase, three important challenges will emerge...

    Provided By University of Notre Dame

  • White Papers // Feb 2012

    Low Latency Relaying Schemes for Next-Generation Cellular Networks

    The reduction in both user and control plane latency is a major goal for next generation (4G) cellular networks, specifically the Long Term Evolution-Advanced (LTE-A) standard. At the same time, relay stations, which introduce additional latency into transmissions, are seen as a potential means to improve cell spectral efficiency and...

    Provided By University of Notre Dame

  • White Papers // Feb 2012

    Secondary Access Policies With Imperfect Sensing in Dynamic Spectrum Access Networks

    The authors consider secondary access policies with imperfect sensing in sensing-based dynamic spectrum access networks. Interference caused by both missed detections as well as the primary user's return to the channel during the secondary transmission are explored. They allow arbitrary distributions for the primary ON/OFF intervals and expand each interval...

    Provided By University of Notre Dame

  • White Papers // Feb 2012

    Multiaccess Communication in the Finite Blocklength Regime

    Although real-world communication networks employ coding schemes with blocklengths as low as several hundred symbols, classical coding theorems of information theory rely on blocklengths approaching infinity. Following a recent line of work on channel dispersion in the finite blocklength regime, the authors use first- and second-order statistics to characterize low-complexity...

    Provided By University of Notre Dame

  • White Papers // Jan 2012

    Method for Privacy-Protecting Display and Exchange of Emergency Information on Mobile Devices

    First responders and emergency care providers make life or death decisions with little to no information about patient's medical problems. Access to a person's medical record could greatly improve the medical care they receive. Challenges to proving this information include finding the correct platform and protecting the patient's privacy. Current...

    Provided By University of Notre Dame

  • White Papers // Jan 2012

    Swarming Under Perfect Consensus Using Integral Action

    Swarming is a collective behavior in which a group of distinct dynamical agents begin to move as a single entity. Swarming behavior has fascinated those interested in how collective actions can emerge from the selfish behavior of individuals in the group. Early examples may be found in physics and biology....

    Provided By University of Notre Dame

  • White Papers // Jan 2012

    Sensorless Sensing in Wireless Networks: Implementation and Measurements

    Multipath fading and shadowing are usually regarded as negative phenomena hindering proper radio communication. Adopting a completely different stance, this paper illustrates that such phenomena enable information harvesting from received signal strength leading to a number of original applications requiring no conventional sensing hardware. The radio itself, provided that it...

    Provided By University of Notre Dame

  • White Papers // Dec 2011

    Emergency Response in Smartphone-Based Mobile Ad-Hoc Networks

    Today's modern mobile devices (e.g., smartphones and tablets) present great potential for building large-scale mobile sensing and information sharing systems which can be highly beneficial to minimize the fatalities of human lives during emergency response. This paper presents a framework, called BREathing rate MONitoring (BREMON) that allows paramedics to monitor...

    Provided By University of Notre Dame

  • White Papers // Oct 2011

    Random Power Control in Poisson Networks

    This paper studies power control strategies in interference-limited wireless networks with Poisson distributed nodes. The authors concentrate on two sets of strategies: Single-Node Optimal Power Control (SNOPC) strategies and Nash Equilibrium Power Control (NEPC) strategies. SNOPC strategies maximize the expected throughput of the power controllable link given that all the...

    Provided By University of Notre Dame

  • White Papers // Oct 2011

    Work Queue + Python: A Framework for Scalable Scientific Ensemble Applications

    Even with the increase in the number and variety of computer resources available to research scientists today, it is still challenging to construct scalable distributed applications. To address this issue, the authors developed Work Queue, a flexible master/- worker framework for building large scale scientific ensemble applications that span many...

    Provided By University of Notre Dame

  • White Papers // Oct 2011

    Converting a High Performance Application to an Elastic Cloud Application

    Over the past decade, high performance applications have embraced parallel programming and computing models. While parallel computing offers advantages such as good utilization of dedicated hardware resources, it also has several drawbacks such as poor fault-tolerance, scalability, and ability to harness available resources during run-time. The advent of cloud computing...

    Provided By University of Notre Dame

  • White Papers // Oct 2011

    Communications Overhead as the Cost of Constraints

    This paper speculates on a perspective for studying overhead in communication systems that contrasts the traditional viewpoint that overhead is the "Non-data" portion of transmissions. By viewing overhead as the cost of constraints imposed on a system, information-theoretic techniques can be used to obtain fundamental limits on overhead information, and...

    Provided By University of Notre Dame

  • White Papers // Oct 2011

    On the Use of an Algebraic Language Interface for Waveform Definition

    The authors discuss implementation aspects of a software-defined radio system that allows the user to define waveforms using an algebraic language interface, currently as an extension to C++. Current software-defined radio systems provide waveform definitions through a combination of a graphical interface, markup language, interpreted script, and compiled code. No...

    Provided By University of Notre Dame

  • White Papers // Oct 2011

    Seamless Dynamic Runtime Reconfiguration in a Software-Defined Radio

    The authors discuss implementation aspects of a software-defined radio system that allows for dynamic waveform reconfiguration during runtime without interrupting data-flow processing. Traditional software-defined radio systems execute a waveform statically, exactly as it is programmed. Reconfiguration is provided by executing a different waveform, which requires the system to stop processing...

    Provided By University of Notre Dame

  • White Papers // Sep 2011

    Interference in Ad Hoc Networks With General Motion-Invariant Node Distributions

    In this paper, the authors derive the tail properties of interference for any stationary and isotropic spatial distribution of transmitting nodes. Previously the properties of interference were known only when the nodes are distributed as a homogeneous Poisson point process on the plane. They show the effect of a singular...

    Provided By University of Notre Dame

  • White Papers // Sep 2011

    Bounds on Information Propagation Delay in Interference-Limited ALOHA Networks

    In a wireless network the set of transmitting nodes changes frequently because of the MAC scheduler and the traffic load. Analyzing the connectivity of such a network using static graphs would lead to pessimistic performance results. In this paper, the authors consider an ad hoc network with half-duplex radios that...

    Provided By University of Notre Dame

  • White Papers // Sep 2011

    Path Loss Exponent Estimation in Large Wireless Networks

    In wireless channels, the Path Loss Exponent (PLE) has a strong impact on the quality of the links, and hence, it needs to be accurately estimated for the efficient design and operation of wireless networks. This paper addresses the problem of PLE estimation in large wireless networks, which is relevant...

    Provided By University of Notre Dame

  • White Papers // Sep 2011

    Effect of Network Geometry and Interference on Consensus in Wireless Networks

    The authors study the convergence of the average consensus algorithm in wireless networks in the presence of interference. It is well-known that convergence of the consensus algorithm improves with network connectivity. However, from a networking standpoint, highly connected wireless networks may have lower throughput because of increased interference. This raises...

    Provided By University of Notre Dame

  • White Papers // Sep 2011

    On Consensus Over Stochastically Switching Directed Topologies

    The authors consider average consensus algorithms executed over stochastically varying communication topologies that may be unbalanced. It is known that the state values will reach consensus, under fairly weak conditions. However, the consensus value is a random variable. They provide concentration bounds for the distance of the state vector from...

    Provided By University of Notre Dame

  • White Papers // Sep 2011

    Dynamic Connectivity and Packet Propagation Delay in ALOHA Wireless Networks

    The authors consider an ad hoc network which uses multihop and slotted ALOHA for its MAC contention. They then formulate the minimum time required for a packet to reach the destination from the origin. They define this delay as the minimum time required for a causal path to form between...

    Provided By University of Notre Dame

  • White Papers // Sep 2011

    Geometry, Connectivity, and Broadcast Transport Capacity of Random Networks With Fading

    In ad hoc networks with random node distribution, the underlying point process model and the channel fading process are usually considered separately. The authors provide a unified framework for the geometric characterization of fading by incorporating the fading process into the point process model. Concretely, assuming nodes are distributed in...

    Provided By University of Notre Dame

  • White Papers // Sep 2011

    On Stability Across a Gaussian Product Channel

    The authors present sufficient conditions for stabilizing a scalar discrete-time LTI plant in the mean squared sense when a sensor transmits the plant state information to a remotely placed controller across a Gaussian product channel. The Gaussian product channel models a continuous-time waveform Gaussian channel, where the encoder transmits information...

    Provided By University of Notre Dame

  • White Papers // Aug 2011

    Secure and Verifiable Outsourcing of Large-Scale Biometric Computations

    Cloud computing services are becoming prevalent and readily available today, bringing to one economies of scale and making large scale computation feasible. Security and privacy considerations, however, stand on the way of fully utilizing the benefits of such services and architectures. In this paper, the authors address the problem of...

    Provided By University of Notre Dame

  • White Papers // Aug 2011

    Superposition Coding Strategies: Design and Experimental Evaluation

    The authors design and implement a software-radio system for Superposition Coding (SC), a multiuser transmission scheme that deliberately introduces interference among user signals at the transmitter, using a library of off-the-shelf point-to-point channel codes. They experimentally determine the set of rate-pairs achieved by this transmission scheme under a packet-error constraint....

    Provided By University of Notre Dame

  • White Papers // Aug 2011

    Notre Dame Marketing Professor Recognized With Lifetime Achievement Award

    The author has spent much of his 35-year academic career researching and teaching in the area of ethical concerns in marketing, publishing research papers and books about sustainability and corporate social responsibility as far back as the 1970s. The University of Notre Dame professor recently was honored for his contributions...

    Provided By University of Notre Dame

  • White Papers // Aug 2011

    On the Optimal Block Length for Joint Channel and Network Coding

    Channel coding alone is not sufficient to reliably transmit a message of finite length from a source to one or more destinations. To ensure that no data is lost, channel coding on the physical layer needs to be combined with rateless erasure correcting schemes such as Automatic Repeat reQuest (ARQ)...

    Provided By University of Notre Dame

  • White Papers // Aug 2011

    Flying Bosses: New Study Highlights Why CEO Pilots Make Good Leaders

    The kind of risk-seeking behavior that motivates certain people to fly personal aircraft may also make them effective corporate leaders, according to a new study co-authored by professors from the University of Notre Dame and the University of Oregon. Merging finance and psychology research to explore the role that genetics...

    Provided By University of Notre Dame

  • White Papers // Aug 2011

    Research Shows Men Get Ahead For Being "Disagreeable" In The Workplace; Women Don't

    In the workplace they do, according to new research co-authored by University of Notre Dame Management Professor Timothy Judge. The paper shows a strong negative relationship between agreeableness and earnings for men. The more agreeable a man is, the less he will earn. For women, there is essentially no relationship...

    Provided By University of Notre Dame

  • White Papers // Jul 2011

    Interference and Outage in Mobile Random Networks: Expectation, Distribution, and Correlation

    In mobile networks, distance variations caused by node mobility generate fluctuations in the channel gains. Such fluctuations can be treated as another type of fading besides multi-path effects. In this paper, the interference statistics in mobile random networks are characterized by mapping the distance variations of mobile nodes to the...

    Provided By University of Notre Dame

  • White Papers // Jul 2011

    Percolation in the Secrecy Graph

    Secrecy graphs model the connectivity of wireless networks under secrecy constraints. Directed edges in the graph are present whenever a node can talk to another node securely in the presence of eavesdroppers. In the case of infinite networks, a critical parameter is the maximum density of eavesdroppers that can be...

    Provided By University of Notre Dame

  • White Papers // Jul 2011

    Notre Dame MBA Joins Fort? Foundation To Support Women In Business

    The University of Notre Dame MBA, a leading graduate business program located in the Mendoza College of Business, has joined Fort? Foundation, a consortium of leading multinational corporations, the Graduate Management Admission Council? (GMAC?) and top global business schools. The Fort? Foundation is the leading organization that provides a national...

    Provided By University of Notre Dame

  • White Papers // Jul 2011

    News Corp. Phone Hacking Scandal Now Political

    The author says the phone hacking scandal surrounding Rupert Murdoch's News Corporation has become more of a political story than a business story. "What's been exposed here is the overly-cozy relationship between senior political figures, the metropolitan police and the tabloid press in London," the author says. "The usual forms...

    Provided By University of Notre Dame

  • White Papers // Jul 2011

    Consider Yourself Ethical? Think Again, Says New Research

    When confronted with an ethical dilemma, most of us like to think we would stand up for our principles. But we are not as ethical as we think we are, according to the author, the Rex and Alice A. Martin Professor of Business Ethics at the University of Notre Dame's...

    Provided By University of Notre Dame

  • White Papers // Jul 2011

    Improving Control-Performance Across AWGN Channels Using a Relay Node

    Consider an unstable linear time invariant system in which the sensor transmits information to a controller across an additive white Gaussian noise channel. The designer can optionally utilize a relay node to assist the controller; however the total transmission power consumed by the sensor and the relay node is constant....

    Provided By University of Notre Dame

  • White Papers // Jul 2011

    Executive Education Awards Recognize Corporate Partners, Faculty

    An orthopedic manufacturer, an improve group and a CEO from an investment bank in Puerto Rico were among the diverse group of award recipients during the annual Notre Dame Executive Education awards banquet, held June 14 inside Purcell Pavilion at the Joyce Center at the University of Notre Dame. "The...

    Provided By University of Notre Dame

  • White Papers // Jul 2011

    Low-Complexity Incremental Use of Multiple Transmitters in Wireless Communication Systems

    In this paper, the authors develop and analyze low-complexity approaches that they call incremental Multiple-Input Multiple-Output (IMIMO) for exploiting multiple antennas for reliable high-rate communications in wireless systems. The proposed schemes leverage consecutive uses of a single transmit antenna combined with Automatic Repeat reQuest (ARQ) feedback, possibly with multiple receive...

    Provided By University of Notre Dame

  • White Papers // Jul 2011

    Service Sharing in Mobile Sensing Systems

    Today's modern mobile devices, (such as smartphones and tablets) present great potential for growth of many novel, powerful, but also highly demanding applications. However, most mobile devices/users operate in isolation from one another, i.e., they are not aware of the presence of other devices in their proximity. There are numerous...

    Provided By University of Notre Dame

  • White Papers // Jul 2011

    Former Naval Officer Will Head Notre Dame Business Undergrad Program

    The author, formerly a professor of Naval Science at the University of Notre Dame, will become the senior director of Undergraduate Studies at the Mendoza College of Business as of July 1. A graduate of the United States Naval Academy, the author earned a Master of Science degree in Management...

    Provided By University of Notre Dame

  • White Papers // Jun 2011

    Carolyn Woo Named CEO/President Of Catholic Relief Services

    Carolyn Y. Woo, Martin J. Gillen Dean of the University of Notre Dame's Mendoza College of Business, will leave the University to serve as president and CEO of Catholic Relief Services (CRS), effective Jan. 1, 2012. Woo assumed the deanship in 1997 of the Mendoza College, which currently is ranked...

    Provided By University of Notre Dame

  • White Papers // Jun 2011

    An Online Holistic Scheduling Framework for Energy-Constrained Wireless Real-Time Systems

    The authors consider wireless real-time systems that execute computationally-intensive applications and must transmit packets over the network in a timely manner. Existing methods do not consider the importance (i.e., urgency) of a packet as perceived by end users in conjunction with energy consumption, real-time task deadlines, and packet deadlines, inadvertently...

    Provided By University of Notre Dame

  • White Papers // Oct 2010

    An Integrated Monitoring System for Smartphones

    Much work has been done in the area of monitoring on traditional systems, such as servers, workstations and laptops. User and application behavior has also been studied on a wide range of platforms. Recently, smartphones have seen a dramatic increase in availability and adoption. New monitoring tools are needed to...

    Provided By University of Notre Dame

  • White Papers // Jan 2010

    Local Delay in Static and Highly Mobile Poisson Networks With ALOHA

    Communication between two neighboring nodes is the most basic operation in wireless networks. Yet very little research has focused on the local delay, defined as the mean time it takes a node to connect to its nearest neighbor. In this paper, the authors derive the local delay in Poisson networks...

    Provided By University of Notre Dame

  • White Papers // Sep 2009

    Implementation and Experimental Results of Superposition Coding on Software Radio

    In theory, multi-user techniques such as Super-Position Coding (SPC) are known to improve throughput in wireless networks. However, in order to understand their practical limitations, it is imperative to actually implement and experiment with such techniques in a realistic setting. In this paper, the authors present the design of a...

    Provided By University of Notre Dame

  • White Papers // Mar 2012

    Fine-Grained Access Control in the Chirp Distributed File System

    Although the distributed file-system is a widely used technology in local area networks, it has seen less use on the wide area networks that connect clusters, clouds, and grids. One reason for this is access control: existing file-system technologies require either the client machine to be fully trusted, or the...

    Provided By University of Notre Dame

  • White Papers // Oct 2011

    Converting a High Performance Application to an Elastic Cloud Application

    Over the past decade, high performance applications have embraced parallel programming and computing models. While parallel computing offers advantages such as good utilization of dedicated hardware resources, it also has several drawbacks such as poor fault-tolerance, scalability, and ability to harness available resources during run-time. The advent of cloud computing...

    Provided By University of Notre Dame

  • White Papers // Oct 2011

    Work Queue + Python: A Framework for Scalable Scientific Ensemble Applications

    Even with the increase in the number and variety of computer resources available to research scientists today, it is still challenging to construct scalable distributed applications. To address this issue, the authors developed Work Queue, a flexible master/- worker framework for building large scale scientific ensemble applications that span many...

    Provided By University of Notre Dame

  • White Papers // Jan 2010

    A Survey of Implementation Efforts and Experimental Design for Cooperative Communications

    Design and analysis of cooperative communication schemes based upon modeling and simulation exist in large quantities in the research literature. Despite this fact, there have been relatively few efforts directed toward implementing and experimentally evaluating such schemes. Cooperative protocols have many components that make them challenging to implement in real-world...

    Provided By University of Notre Dame

  • White Papers // Jan 2010

    Thresholding for Optimal Data Processing in a Software Defined Radio Kernel

    The authors discuss a developing software-defined radio framework and kernel, Surfer, which, among other changes compared with known current frameworks, moves control of when to process a block and how much data to process into the blocks themselves via buffer thresholds. Varying threshold values shows a trade-off between data processing...

    Provided By University of Notre Dame

  • White Papers // Feb 2010

    Sequence Detection Algorithms for Dynamic Spectrum Access Networks

    Spectrum sensing is a critical function for enabling Dynamic Spectrum Access (DSA) in wireless networks that utilize cognitive radio. In DSA networks, unlicensed secondary users can gain access to a licensed spectrum band as long as they do not interfere with primary users. Spectrum sensing is subject to errors in...

    Provided By University of Notre Dame

  • White Papers // Sep 2010

    Sufficient Conditions for Stabilizability Over Gaussian Relay and Cascade Channels

    The authors present sufficient conditions for stabilizability of an unstable linear time invariant scalar system across an additive white Gaussian noise channel, with a relay assisting the observer. They consider two topologies: a Gaussian relay channel, and a cascade of two Gaussian point to point channels. They assume that the...

    Provided By University of Notre Dame

  • White Papers // Feb 2011

    Minimum Delay Communication in Energy Harvesting Systems Over Fading Channels

    The authors consider an energy harvesting wireless system where data is stored in a data buffer and energy is harvested from various sources and stored in an energy buffer. The transmitter tries to minimize a delay criterion, e.g., average delay in the data buffer or probability of overflow, subject to...

    Provided By University of Notre Dame

  • White Papers // Feb 2011

    Limiting Behavior of Receive Antennae Selection

    In this paper, the authors investigate the limiting behavior of receive antenna selection in Single-Input Multiple-Output (SIMO) wireless systems when the number of receive antennas gets very large. Using results on the convergence of the trimmed mean, they show that mutual information converges in distribution to the logarithm of a...

    Provided By University of Notre Dame

  • White Papers // Feb 2011

    Power Allocation in Wireless Systems Subject to Long-Term and Short-Term Power Constraints

    The authors consider several fading channel models for which they aim to maximize ergodic capacity assuming that Channel State Information (CSI) is available at both the receiver and the transmitter. They characterize the optimal power allocation structure in the Single-Input-Single-Output (SISO), Multiple-Input-Single-Output (MISO), and Multiple-Input-Multiple-Output (MIMO) models subject to both...

    Provided By University of Notre Dame

  • White Papers // Jun 2011

    Source-Channel Coding Tradeoff in Multiple Antenna Multiple Access Channels

    The authors investigate channel code rates for communication of finite-dimensional analog sources over a multiple-antenna Multiple Access Channel (MAC) so that the average end-to-end distortions are minimized. Their analysis uses the high-resolution quantization theory for the sources and the high-SNR diversity-multiplexing tradeoff for the MAC. They prove that carefully balanced...

    Provided By University of Notre Dame

  • White Papers // Jul 2011

    Low-Complexity Incremental Use of Multiple Transmitters in Wireless Communication Systems

    In this paper, the authors develop and analyze low-complexity approaches that they call incremental Multiple-Input Multiple-Output (IMIMO) for exploiting multiple antennas for reliable high-rate communications in wireless systems. The proposed schemes leverage consecutive uses of a single transmit antenna combined with Automatic Repeat reQuest (ARQ) feedback, possibly with multiple receive...

    Provided By University of Notre Dame

  • White Papers // Oct 2011

    Communications Overhead as the Cost of Constraints

    This paper speculates on a perspective for studying overhead in communication systems that contrasts the traditional viewpoint that overhead is the "Non-data" portion of transmissions. By viewing overhead as the cost of constraints imposed on a system, information-theoretic techniques can be used to obtain fundamental limits on overhead information, and...

    Provided By University of Notre Dame

  • White Papers // Oct 2011

    On the Use of an Algebraic Language Interface for Waveform Definition

    The authors discuss implementation aspects of a software-defined radio system that allows the user to define waveforms using an algebraic language interface, currently as an extension to C++. Current software-defined radio systems provide waveform definitions through a combination of a graphical interface, markup language, interpreted script, and compiled code. No...

    Provided By University of Notre Dame

  • White Papers // Sep 2011

    On Stability Across a Gaussian Product Channel

    The authors present sufficient conditions for stabilizing a scalar discrete-time LTI plant in the mean squared sense when a sensor transmits the plant state information to a remotely placed controller across a Gaussian product channel. The Gaussian product channel models a continuous-time waveform Gaussian channel, where the encoder transmits information...

    Provided By University of Notre Dame

  • White Papers // Feb 2012

    Multiaccess Communication in the Finite Blocklength Regime

    Although real-world communication networks employ coding schemes with blocklengths as low as several hundred symbols, classical coding theorems of information theory rely on blocklengths approaching infinity. Following a recent line of work on channel dispersion in the finite blocklength regime, the authors use first- and second-order statistics to characterize low-complexity...

    Provided By University of Notre Dame

  • White Papers // Feb 2012

    Low Latency Relaying Schemes for Next-Generation Cellular Networks

    The reduction in both user and control plane latency is a major goal for next generation (4G) cellular networks, specifically the Long Term Evolution-Advanced (LTE-A) standard. At the same time, relay stations, which introduce additional latency into transmissions, are seen as a potential means to improve cell spectral efficiency and...

    Provided By University of Notre Dame

  • White Papers // Feb 2012

    Secondary Access Policies With Imperfect Sensing in Dynamic Spectrum Access Networks

    The authors consider secondary access policies with imperfect sensing in sensing-based dynamic spectrum access networks. Interference caused by both missed detections as well as the primary user's return to the channel during the secondary transmission are explored. They allow arbitrary distributions for the primary ON/OFF intervals and expand each interval...

    Provided By University of Notre Dame

  • White Papers // Sep 2011

    Interference in Ad Hoc Networks With General Motion-Invariant Node Distributions

    In this paper, the authors derive the tail properties of interference for any stationary and isotropic spatial distribution of transmitting nodes. Previously the properties of interference were known only when the nodes are distributed as a homogeneous Poisson point process on the plane. They show the effect of a singular...

    Provided By University of Notre Dame

  • White Papers // Sep 2009

    Implementation and Experimental Results of OFDM-Based Superposition Coding

    In theory, multi-user techniques such as Super-Position Coding (SPC) are known to improve throughput in wireless networks. However, in order to understand their practical limitations, it is imperative to actually implement and experiment with such techniques in a realistic setting. In this paper, the authors present the design of a...

    Provided By University of Notre Dame

  • White Papers // Mar 2010

    Control Design for Switched Systems Using Passivity Indices

    This paper presents a framework for control design of interconnected nonlinear switched systems using passivity and passivity indices. Background material is presented on the concept of passivity indices for continuously-varying systems. The passivity indices are then generalized to apply to switched systems to measure the level of passivity in a...

    Provided By University of Notre Dame

  • White Papers // Apr 2010

    Symmetry in the Design of Large-Scale Complex Control Systems: Some Initial Results Using Dissipativity and Lyapunov Stability

    In this paper, stability conditions for large-scale systems are derived by categorizing agents into symmetry groups and applying local control laws under limited interconnections with neighbors. Particularly, stability for dissipative systems is considered. It is assumed that subsystems are dissipative and stability is studied. Conditions are derived for the max...

    Provided By University of Notre Dame

  • White Papers // Sep 2011

    Bounds on Information Propagation Delay in Interference-Limited ALOHA Networks

    In a wireless network the set of transmitting nodes changes frequently because of the MAC scheduler and the traffic load. Analyzing the connectivity of such a network using static graphs would lead to pessimistic performance results. In this paper, the authors consider an ad hoc network with half-duplex radios that...

    Provided By University of Notre Dame

  • White Papers // Dec 2008

    Lifetime Benefits Through Load Balancing in Homogeneous Sensor Networks

    In routing protocols for wireless sensor networks energy efficiency is of paramount importance. Reliability-oriented protocols discard lossy links to avoid the significant energy cost of packet loss. The downside is that nodes with a particularly favorable channel tend to be overused: this curtails the lifespan of these nodes and may...

    Provided By University of Notre Dame

  • White Papers // Sep 2011

    Path Loss Exponent Estimation in Large Wireless Networks

    In wireless channels, the Path Loss Exponent (PLE) has a strong impact on the quality of the links, and hence, it needs to be accurately estimated for the efficient design and operation of wireless networks. This paper addresses the problem of PLE estimation in large wireless networks, which is relevant...

    Provided By University of Notre Dame

  • White Papers // Nov 2009

    A Roesser Model Based Multidimensional Systems Approach for Grid Sensor Networks

    Using the Givone-Roesser model for m-D systems, a method for distributed information processing in rectangular grid based sensor networks is presented. The method enables a distributed implementation of linear systems on a sensor network. Nonlinearities caused by quantization schemes used for in node computations and inter node communication are modeled....

    Provided By University of Notre Dame

  • White Papers // Sep 2009

    Distributed Averaging in Dense Wireless Networks

    The authors consider the effect of network throughput on the convergence of a specific class of distributed averaging algorithms, called consensus algorithms. These algorithms rely on iterative computation of the desired average by message passing among the nodes. It is thus assumed that the rate of convergence should benefit from...

    Provided By University of Notre Dame

  • White Papers // Sep 2011

    Effect of Network Geometry and Interference on Consensus in Wireless Networks

    The authors study the convergence of the average consensus algorithm in wireless networks in the presence of interference. It is well-known that convergence of the consensus algorithm improves with network connectivity. However, from a networking standpoint, highly connected wireless networks may have lower throughput because of increased interference. This raises...

    Provided By University of Notre Dame

  • White Papers // Sep 2011

    On Consensus Over Stochastically Switching Directed Topologies

    The authors consider average consensus algorithms executed over stochastically varying communication topologies that may be unbalanced. It is known that the state values will reach consensus, under fairly weak conditions. However, the consensus value is a random variable. They provide concentration bounds for the distance of the state vector from...

    Provided By University of Notre Dame

  • White Papers // Aug 2009

    An Event-Triggered Distributed Primal-Dual Algorithm for Network Utility Maximization

    Many problems associated with networked systems can be formulated as Network Utility Maximization (NUM) problems. This paper presents a distributed primal-dual algorithm for the NUM problem that uses event-triggering. Under event triggering, each agent broadcasts to its neighbors when a local "Error" signal exceeds a state dependent threshold. The paper...

    Provided By University of Notre Dame

  • White Papers // Sep 2011

    Dynamic Connectivity and Packet Propagation Delay in ALOHA Wireless Networks

    The authors consider an ad hoc network which uses multihop and slotted ALOHA for its MAC contention. They then formulate the minimum time required for a packet to reach the destination from the origin. They define this delay as the minimum time required for a causal path to form between...

    Provided By University of Notre Dame

  • White Papers // Oct 2008

    Distributed M-D Filtering for Wave Front Detection in Grid Sensor Networks

    This paper presents a method to detect propagating fronts of contaminants in air by employing a rectangular grid sensor network. A linear filtering based distributed algorithm is used for contaminant front detection. Distributed filters are implemented using state space models for 1-D and 2-D systems. Expressions for the amount of...

    Provided By University of Notre Dame

  • White Papers // Sep 2011

    Geometry, Connectivity, and Broadcast Transport Capacity of Random Networks With Fading

    In ad hoc networks with random node distribution, the underlying point process model and the channel fading process are usually considered separately. The authors provide a unified framework for the geometric characterization of fading by incorporating the fading process into the point process model. Concretely, assuming nodes are distributed in...

    Provided By University of Notre Dame

  • White Papers // Mar 2011

    Delay Characterization of Multi-Hop Transmission in a Poisson Field of Interference

    The authors evaluate the end-to-end delay of a multi-hop transmission scheme that includes a source, a number of relays and a destination, in the presence of interferers located according to a Poisson point process. The Medium-Access Control (MAC) protocol considered is a combination of TDMA and ALOHA, according to which...

    Provided By University of Notre Dame

  • White Papers // Feb 2011

    A Statistical Mechanics-Based Framework to Analyze Ad Hoc Networks With Random Access

    Characterizing the performance of ad hoc networks is one of the most intricate open challenges; conventional ideas based on information-theoretic techniques and inequalities have not yet been able to successfully tackle this problem in its generality. Motivated thus, the authors promote the Totally Asymmetric Simple Exclusion Process (TASEP), a particle...

    Provided By University of Notre Dame

  • White Papers // May 2011

    Incremental Use of Multiple Transmitters for Low-Complexity Diversity Transmission in Wireless Systems

    In this paper, the authors develop and analyze low-complexity approaches called Incremental Multiple-Input Multiple-Output (IMIMO) for exploiting multiple antennas for reliable high-rate communications. The proposed schemes leverage consecutive uses of a single transmit antenna combined with Automatic Repeat reQuest (ARQ) feedback. Unlike Multiple-Input Multiple-Output (MIMO) communications without feedback, the schemes...

    Provided By University of Notre Dame