Institute of Electrical and Electronics Engineers

Displaying 321-360 of 7884 results

  • White Papers // Apr 2012

    E2SIW: An Energy Efficient Scheme Immune to Wormhole Attacks in Wireless Ad Hoc Networks

    Wormhole attacks are considered as a severe security threat in multi-hop wireless ad hoc networks. In this paper, the authors propose an Energy-Efficient Scheme Immune to Wormhole attacks (their so-called E2SIW). This protocol uses the location information of nodes to detect the presence of a wormhole, and in case a...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Apr 2012

    The Dynamic Granularity Memory System

    Chip multiprocessors enable continued performance scaling with increasingly many cores per chip. As the throughput of computation outpaces available memory bandwidth, however, the system bottleneck will shift to main memory. The authors present a memory system, the Dynamic Granularity Memory System (DGMS), which avoids unnecessary data transfers, saves power, and...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Apr 2012

    Lane Decoupling for Improving the Timing-Error Resiliency of Wide-SIMD Architectures

    A significant portion of the energy dissipated in modern integrated circuits is consumed by the overhead associated with timing guard-bands that ensure reliable execution. Timing speculation, where the pipeline operates at an unsafe voltage with any rare errors detected and resolved by the architecture, has been demonstrated to significantly improve...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Apr 2012

    The JavaSPI Framework for Security Protocol Implementation

    Security protocols are distributed algorithms that run over untrusted networks with the aim of achieving security goals, such as mutual authentication of two protocol parties. This paper presents JavaSPI, a \"Model-driven\" development framework that allows the user to reliably develop security protocol implementations in Java, starting from abstract models that...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Apr 2012

    Analysis and Design of Tuned Turbo Codes

    Turbo codes and Multiple Parallel Concatenated Codes (MPCCs) perform very close to the Shannon limit with suboptimum iterative decoding, but the corresponding code ensembles are asymptotically bad in the sense that their minimum (Hamming) distance does not grow linearly with block length. It has been widely observed that there exists...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Apr 2012

    FemtoCaching: Wireless Video Content Delivery Through Distributed Caching Helpers

    The authors propose and analyze a novel way for increasing the area spectral efficiency of video transmission in cellular communications systems. Small base stations called helpers with low-rate backhaul but high storage capacity cache popular video files. Mobile stations requesting video files receive them via short-range transmissions from helpers, if...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Apr 2012

    Femtocaching and Device-to-Device Collaboration: A New Architecture for Wireless Video Distribution

    The authors present a new architecture to handle the ongoing explosive increase in the demand for video content in wireless networks. It is based on distributed caching of the content in femto-basestations with small or non-existing backhaul capacity but with considerable storage space, called helper nodes. They also consider using...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Apr 2012

    Connectivity of Large Wireless Networks Under a Generic Connection Model

    Connectivity is one of the most fundamental properties of wireless multi-hop networks. A network is said to be connected if there is a path between any pair of nodes. Extensive research has been done on connectivity problems using the well-known random geometric graph and the unit disk connection model, which...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Apr 2012

    Second-Order Resolvability, Intrinsic Randomness, and Fixed-Length Source Coding for Mixed Sources: Information Spectrum Approach

    The second-order achievable asymptotics in typical random number generation problems such as resolvability, intrinsic randomness, fixed-length source coding is considered. In these problems, several researchers have derived the first-order and the second-order achievability rates for general sources using the information spectrum methods. Although these formulas are general, their computation is...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Apr 2012

    Signal Shaping and Modulation for Optical Wireless Communication

    In this paper, a signal shaping framework for Optical Wireless Communication (OWC) is proposed. The framework is tailored to the single-carrier pulse modulation techniques, such as multi-level Pulse Position Modulation (-PPM) and multi-level Pulse Amplitude Modulation (-PAM), and to multi-carrier transmission realized through multi-level Quadrature Amplitude Modulation (-QAM) with Orthogonal...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Apr 2012

    Clipping Noise in OFDM-Based Optical Wireless Communication Systems

    In this paper, the impact of clipping noise on Optical Wireless Communication (OWC) systems employing Orthogonal Frequency Division Multiplexing (OFDM) is investigated. The two existing Optical OFDM (O-OFDM) transmission schemes, Asymmetrically Clipped Optical OFDM (ACO-OFDM) and Direct Current-biased Optical OFDM (DCO-OFDM), are studied. Time domain signal clipping generally results from...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Apr 2012

    Improving Channel Estimation Accuracy in OFDM System Using MATLAB Simulation

    This paper is to improve channel estimation accuracy in OFDM system because channel state information is required for signal detection at receiver and its accuracy affects the overall performance of system and it is essential to improve the channel estimation for more reliable communications. OFDM system was chosen in this...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Training Symbol Design for Channel Estimation and IQ Imbalance Compensation in OFDM Systems

    In this paper, training symbol designs for estimation of frequency selective channels and compensation of In-phase (I) and Quadrature (Q) imbalances on OFDM transmitters and receivers are studied. The authors utilize Cross Entropy (CE) optimization techniques together with convex optimization to design training sequence that minimizes the channel estimate Mean...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Suboptimal Power Allocation for a Two-Path Successive Relay System with Full Interference Cancellation

    Although power allocation considerably affects the Symbol Error Rate (SER) performance of a Two-Path Successive Relay System (TPSRS), it is not yet studied in a Full Interference Cancellation (FIC) scenario. In this paper, the authors develop a suboptimal power allocation scheme for the TPSRS-FIC through minimizing an SER-based cost function....

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Utility-Based Dynamic Multi-Service Bandwidth Allocation in Heterogeneous Wireless Networks

    In this paper, the authors present a dynamic bandwidth allocation scheme for multiple services in heterogeneous networks. A utility function is introduced first, whose parameters are determined by the modified multi-state Analytic Hierarchy Process (AHP) which adapts to different load levels according to dynamic thresholds. Based on this, a bandwidth...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    A Physical-Layer Network Coding Scheme Based on Linear MIMO Detection

    A Physical-layer Network Coding (PNC) scheme based on MIMO linear detection is proposed in this paper for a two-way relay channel with a multi-antenna relay. The authors apply a real-valued linear combiner to the output symbols of the MIMO linear detector to obtain a superimposed constellation for which the labeling...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Performance Debugging in the Large Via Mining Millions of Stack Traces

    Given limited resource and time before software release, development-site testing and debugging become more and more insufficient to ensure satisfactory software performance. As a counterpart for debugging in the large pioneered by the Microsoft Windows Error Reporting (WER) system focusing on crashing/hanging bugs, performance debugging in the large has emerged...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Optimizing Channel Access for Event-Driven Wireless Sensor Networks: Analysis and Enhancements

    The authors study the problem of medium access control in domain of event-driven Wireless Sensor Networks (WSN). In this kind of WSN, sensor nodes send data to sink node only when an event occurs in the monitoring area. The nodes in this kind of WSN encounter correlated traffic as a...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Data Dissemination in Wireless Networks With Network Coding

    The authors investigate the use of network coding for information dissemination over a wireless network. Using network coding allows for a simple, distributed and robust algorithm where nodes do not need any information from their neighbors. In this paper, they analyze the time needed to diffuse information throughout a network...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Distributed Space Time Coding for Wireless Two-Way Relaying

    The authors consider the wireless two-way relay channel, in which two-way data transfer takes place between the end nodes with the help of a relay. For the Denoise-aNd-Forward (DNF) protocol, it was shown by Koike-Akino et. al. that adaptively changing the network coding map used at the relay greatly reduces...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Balancing the Trade-Offs Between Query Delay and Data Availability in MANETs

    In Mobile Ad hoc NETworks (MANETs), nodes move freely and link/node failures are common, which leads to frequent network partitions. When a network partition occurs, mobile nodes in one partition are not able to access data hosted by nodes in other partitions, and hence significantly degrade the performance of data...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Mitigating Routing Misbehavior in Disruption Tolerant Networks

    In Disruption Tolerant Networks (DTNs), selfish or malicious nodes may drop received packets. Such routing misbehavior reduces the packet delivery ratio and wastes system resources such as power and bandwidth. Although techniques have been proposed to mitigate routing misbehavior in mobile ad hoc networks, they cannot be directly applied to...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    On Optimal Link Activation With Interference Cancellation in Wireless Networking

    A fundamental aspect in performance engineering of wireless networks is optimizing the set of links that can be concurrently activated to meet given Signal-to-Interference-and-Noise Ratio (SINR) thresholds. The solution of this combinatorial problem is the key element in scheduling and cross-layer resource management. Previous works on link activation assume single-user...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    The Overall Balance Between Cooperation and Interference for a Class of Wireless Networks

    This paper investigates the benefits of cooperation in large wireless networks with multiple sources and relays, where the nodes form an homogeneous Poisson point process. The source nodes may dispose of their nearest neighbor from the set of inactive nodes as their relay. Although cooperation can potentially lead to significant...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    A Survey on Security for Mobile Devices

    Now-a-days, mobile devices are an important part of the authors' everyday lives since they enable the users to access a large variety of ubiquitous services. In recent years, the availability of these ubiquitous and mobile services has significantly increased due to the different form of connectivity provided by mobile devices,...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Reinforcement Learning Strategies for Self-Organized Coverage and Capacity Optimization

    Traditional manual procedures for coverage and capacity optimization are complex and time consuming due to the increasing complexity of cellular networks. This paper presents reinforcement learning strategies for self-organized coverage and capacity optimization through antenna downtilt adaptation. The authors analyze different learning strategies for a Fuzzy Q-Learning based solution in...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Topology Control in Multihop Wireless Networks With Multi-Beam Smart Antennas

    Smart (directional) antennas can be deployed in a wireless network to enhance the capacity of the network by forming one or multiple beams only towards intended receivers. In this paper, the authors focus on the topology control approach for efficient communications in a wireless network with multi-beam smart antennas. This...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    DEAR: Delay-Bounded Energy-Constrained Adaptive Routing in Wireless Sensor Networks

    Reliability and energy efficiency are critical issues in wireless sensor networks. In this paper, the authors study Delay-bounded Energy-constrained Adaptive Routing (DEAR) problem with reliability, differential delay, and transmission energy consumption constraints in wireless sensor networks. They aim to route the connections in a manner such that link failure does...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Integrating Routing with Content Delivery Networks

    Several research efforts are underway to associate content "Names" to the network space. There is a general belief that video and other types of cacheable content are going to continue to demand ever larger portions of a network's bandwidth. Technologies that enable network link bandwidth increases are struggling to keep...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    On Exploiting Flow Allocation With Rate Adaptation for Green Networking

    Network power consumption can be reduced considerably by adapting link data rates to their offered traffic loads. In this paper, the authors exploit how to leverage rate adaptation for green networking by studying the following flow allocation problem in wired networks: given a set of candidate paths for each end-to-end...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Energy-Efficient Collaborative Sensing With Mobile Phones

    Mobile phones with a rich set of embedded sensors enable sensing applications in various domains. In this paper, the authors propose to leverage cloud-assisted collaborative sensing to reduce sensing energy consumption for mobile phone sensing applications. They formally define a minimum energy sensing scheduling problem and present a polynomial-time algorithm...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Sensing and Probing Cardinalities for Active Cognitive Radios

    In a cognitive radio network, Opportunistic Spectrum Access (OSA) to the underutilized spectrum involves not only sensing the spectrum occupancy, but also probing the channel quality in order to identify an idle and good channel for data transmission - particularly if a large number of channels is open for secondary...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Large Families of Asymptotically Optimal Two-Dimensional Optical Orthogonal Codes

    Nine new 2-D OOCs are presented here, all sharing the common feature of a code size that is much larger in relation to the number of time slots than those of constructions appearing previously in the literature. Each of these constructions is either optimal or asymptotically optimal with respect to...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Green Resource Allocation to Minimize Receiving Energy in OFDMA Cellular Systems

    Advanced cellular systems supporting ultra high traffic (e.g., 1 Gbps) utilize aggressive communication technologies to User Equipment (UE) and thus induce high-energy consumption. To reduce UE energy consumption, the authors note that in OFDMA systems, transmissions to one UE can be scheduled into fewer time slots due to multiple available...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Rate-Delay Enhanced Multipath Transmission Scheme Via Network Coding in Multihop Networks

    Distinct from the existing rate-reliability results, a novel multipath transmission scheme is proposed to enhance the rate-delay performance in multihop networks by employing network coding at the source. This scheme provides new rate-delay tradeoffs with fine granularity for rate maximization and is adaptive to Quality-of-Service (QoS) requirements. With the increasing...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    CommonCode: A Code-Reuse Platform for Wireless Network Experimentation

    Experimentation of a wireless network protocol over the air is of significant interest. However, it is more rarely performed than simulation because of the difficulties in coding and debugging as well as lack of scalability and repeatability. In this paper, the concept of a code-reuse platform making use of a...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Energy-Aware Autonomic Resource Allocation in Multitier Virtualized Environments

    With the increase of energy consumption associated with IT infrastructures, energy management is becoming a priority in the design and operation of complex service-based systems. At the same time, service providers need to comply with Service Level Agreement (SLA) contracts which determine the revenues and penalties on the basis of...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2012

    Weighted Sum Rate Maximization of Correlated MISO Broadcast Channels Under Linear Precoding: A Large System Analysis

    In this paper, the authors study the iterative Weighted Sum Rate (WSR) maximizing linear precoder algorithm proposed by Christensen et al. in large correlated MISO broadcast channels. They propose a novel approximation of the Signal-to-Interference plus Noise Ratio (SINR) at every iteration. Moreover, for independent and identical distributed channels the...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Feb 2012

    Belief Consensus Algorithms for Distributed Target Tracking in Wireless Sensor Networks

    In distributed target tracking in Wireless Sensor Networks (WSN), agreement on the target state is usually achieved by the construction and maintenance of a communication path. Such an approach lack robustness to failures, and is not applicable to asynchronous networks. Recently, methods have been proposed that can solve these problems...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Feb 2012

    A New Convergent Identity System Based on EAP-TLS Smart Cards

    In this paper, the authors present a new identity system, named SSL-Identity, working with EAP-TLS smart cards. It details an innovative technology based on tiny SSL stacks deployed in billions of such devices embedded in USB dongles or mobile phones, and comments first experimental results. SSL-Identity is convergent because it...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Feb 2012

    Cooperative Geographic Routing With Radio Coverage Extension for SER-Constrained Wireless Relay Networks

    Cooperative communication for wireless networks has been extensively investigated from the perspective of physical layer design. However, the impact of physical-layer cooperation on the network-layer routing design still remains unclear. In this paper, the authors examine the potential benefit of radio coverage extension from cooperation, and present how to incorporate...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Feb 2012

    Opportunistic Cooperative Networking: To Relay or Not to Relay?

    In this paper, the authors consider Opportunistic Cooperative Networking (OCN) in wireless ad hoc networks, with a focus on characterizing the desired tradeoff between the probing cost for establishing cooperative relaying and hence higher throughput via opportunistic cooperative networking. Specifically, opportunistic cooperative networking is treated as an optimal stopping problem...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Feb 2012

    Distributed Best-Relay Selection for Improving TCP Performance Over Cognitive Radio Networks: A Cross-Layer Design Approach

    In Cognitive Radio (CR) networks, cooperative relaying is emerging as a key technology to improve the performance of secondary users (SUs), while ensuring the quality of service of primary transmissions. Most previous work in CR relay networks concentrates on maximizing physical layer data rate as a design criterion. However, the...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Feb 2012

    Cooperative Strategies in Wireless Relay Networks

    In this paper, the authors explain the cooperative strategies of relay stations in wireless relay networks. In such networks, relay stations distributed across the network and centrally controlled by the base station can be exploited to form cooperative antenna arrays. They show that via relay station cooperation, the achievable downstream...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Feb 2012

    MAC Centered Cooperation - Synergistic Design of Network Coding, Multi-Packet Reception, and Improved Fairness to Increase Network Throughput

    The authors design a cross-layer approach to aid in developing a cooperative solution using Multi-Packet Reception (MPR), Network Coding (NC), and Medium ACcess (MAC). They construct a model for the behavior of the IEEE 802.11 MAC protocol and apply it to key small canonical topology components and their larger counterparts....

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Feb 2012

    Spectrum Harvesting and Sharing in Multi-Hop CRNs Under Uncertain Spectrum Supply

    The essential impediment to apply Cognitive Radio (CR) technology for efficient spectrum utilization lies in the uncertainty of licensed spectrum supply. In this paper, the authors propose a novel architecture for spectrum harvesting and sharing, and investigate the joint routing and frequency scheduling problem in multi-hop Cognitive Radio Networks (CRNs)...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Feb 2012

    Joint Zero-Forcing Based Precoder Design for QoS-Aware Power Allocation in MIMO Cooperative Cellular Network

    In this paper, the authors explain about the cellular system scenario where multiple data streams originating from a Base Station (BS) targeted to multiple cell-edge Mobile Stations (MSs) are transmitted via preinstalled cooperative Relay Stations (RSs) with multiple antennas. Their objective is to guarantee Quality-of-Service (QoS) in terms of predefined...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Feb 2012

    Decomposed LT Codes for Cooperative Relay Communications

    Forward Error Correction (FEC) is commonly adopted in cooperative relay communications to ensure link-layer communication reliability. Among those schemes, rate-less fountain codes, such as Luby Transform (LT) codes, are favorable for their low complexity and rate adaptability to channel fading dynamics. However, the cooperative transmission schemes based on primitive fountain...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Jan 2012

    Towards Optimal Adaptive UFH-Based Anti-Jamming Wireless Communication

    Anti-jamming communication without pre-shared secrets has gained increasing research interest recently and is commonly tackled by utilizing the technique of Uncoordinated Frequency Hopping (UFH). Existing researches, however, are almost all based on ad hoc designs of frequency hopping strategies, mainly due to lack of theoretical foundations for scheme performance evaluation....

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    Joint Call and Packet Level Performance Analysis of CAC Strategies for VoIP Traffic in Wireless

    Call Admission Control (CAC) functionality is a critical requirement for guarantee the desired Quality of Service (QoS) for voice calls in IP-based wireless networks. In this paper, three different CAC strategies for Voice over IP (VoIP) traffic over Wireless Access Networks with packet buffering are mathematically analyzed through a joint...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    A Hybrid Positioning Approach by UWB Radio Communication Systems for Non Line-Of-Sight Conditions

    Recently, Impulse Radio Ultra Wide-Band (IR-UWB) signaling has become popular for providing precise location accuracy for device localization in the indoor environment due to its large bandwidth and high time resolution while performing ultra-high capacity of transmission. Received signal's Time-Of-Arrival (TOA) based real time ranging system is widely used for...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    Efficient State Estimation with Energy Harvesting and Fairness Control Using Stochastic Optimization

    Wireless Sensor Networks (WSN) intended for critical applications often rely on energy harvesting batteries, yet also require backup batteries to ensure uninterrupted operation. An optimal algorithm for resource allocation in such WSN used for state estimation is presented. The resulting state estimate approaches a minimum accuracy constraint with efficient use...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    Modeling and Generation of Space-Time Correlated Signals for Sensor Network Fields

    In the past few years, a large number of networking protocols for data gathering through aggregation, compression and recovery in Wireless Sensor Networks (WSNs) have utilized the spatio-temporal statistics of real world signals in order to achieve good performance in terms of energy savings and improved signal reconstruction accuracy. However,...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    Closed-form expressions of optimal short PR FMT prototype filters

    The Filtered Multi-Tone (FMT) modulation can be seen as a simple extension of the OFDM modulation. Indeed, it can be efficiently realized as a Discrete Fourier Transform (DFT)-based transceiver. However, to avoid a significant increase of its computational complexity the FMT has to be implemented with short prototype filters. In...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    Lightweight Source Anonymity in Wireless Sensor Networks

    In many applications of Wireless Sensor Networks (WSN), the source of an event needs to be protected. In resource constrained WSN, providing source anonymity is a challenging task. A traditional approach for hiding source in WSN is to let all nodes generate dummy data packets even if they have no...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    Maximizing the Fair Allocation of Opportunistic Spectrum for CR Ad hoc Networks

    Cognitive Radios (CRs) address spectrum scarcity and under-utilization of the spectrum. Allocating spectrum to CR nodes in a network is neither easy nor straight-forward since spectrum availability is space and time-varying. The Link layer always sets up communication between nodes in a CR ad hoc network by allocating the available...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    Pulse Switching for Static Event Sensing in Sensor Networks

    In this paper, the authors present a novel energy-efficient pulse switching protocol for ultra light-weight wireless network applications. The key idea is to abstract a single pulse, as opposed to multi-bit packets, as the information exchange mechanism. Pulse switching is shown to be sufficient for event sensing applications with binary...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    Frequency Hopping Based Wireless Metering in Smart Grid: Code Design and Performance Analysis

    To address the security and performance challenges, a novel smart grid communication system based on the Frequency-Hopping (FH) technology is investigated in this paper. A new FH sequence set with various levels of Hamming cross-correlation values is proposed for this system in order to endow the power users various Qualities...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    Frequency Division Duplex Time Reversal

    In this paper, the authors propose a new pre-coding technique called Frequency Division Duplex Time Reversal (FDD TR) for Multiple Input Multiple Output (MIMO) wireless communications, in Frequency Division Duplex (FDD) mode. FDD TR relies on unquantized uncoded channel feedback. It is compared to Time Reversal (TR), 1bit Time Reversal...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    Beneficial Transparent Deployment of SCTP: The Missing Pieces

    The Internet-wide deployment of new transport protocols such as the Stream Control Transmission Protocol (SCTP) is a difficult matter. While SCTP could be beneficial in many cases, it is still a major challenge to enable applications to use the new protocol. The authors believe that its deployment could be significantly...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    Transmit and Receive Weights in Vector Coding with Channel Estimation Error and Feedback Delay

    Vector Coding (VC) is a transmission scheme that can obtain path diversity gain while orthogonalizing multiple symbols. It has been shown that VC can provide good Bit Error Rate (BER) performance compared to Orthogonal Frequency Division Multiplexing (OFDM). In addition VC has been proven to be the optimal partition of...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    Stable Sleeping in DSL Broadband Access: Feasibility and Tradeoffs

    Energy efficient and stable operation of the DSL broadband access infrastructure has become an essential part of the emerging trend towards green communications. One promising means to obtain energy savings is the use of low power "Sleep Modes", putting DSL modems to sleep when they are not used. Executing the...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    A Mesh Network over a Semi-Transparent Satellite

    In the satellite communications component of the future Internet, Peer-To-Peer mesh connectivity of satellite terminals is an impellent necessity. In particular, delay sensitive applications such as real-time multimedia, collaborative conferencing and cellular backhauling are appealing use-cases for adopting mesh network topologies. Moreover, the use of a single satellite hop for...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    VNR Algorithm: A Greedy Approach For Virtual Networks Reconfigurations

    In this paper, the authors address the problem of virtual network reconfiguration. In their previous work on virtual network embedding strategies, they found that most virtual network rejections were caused by bottlenecked substrate links while peak resource use is equal to 18%. These observations lead them to propose a new...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    geoDTN: Geographic Routing in Disruption Tolerant Networks

    In this paper, the authors present a disruption tolerant routing algorithm based on geographic location information, which improves upon the hop count compared to the current state of the art by up to a factor of three in large scale human networks. Leveraging only the history of geographic movement patterns...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    Follow the Trail: a Search Strategy in Event-driven Wireless Sensor and Actor Networks

    In wireless sensor and actor networks, when an event is detected, the sensor node needs to transmit an event report to inform the actors. Since the actors move in the network to execute missions, their location information is hard to be acquired and always unavailable to the sensor nodes. In...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    Cooperative Sybil Attack Detection for Position Based Applications in Privacy Preserved VANETs

    In this paper, the authors propose a security protocol to detect sybil attacks for position based applications in privacy preserved Vehicular Ad-hoc NETworks (VANETs). Vehicles in their protocol identify sybil attacks locally in a cooperative way by examining the rationality of vehicles' positions to their own neighbors. The attack detection...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    A Privacy Preserving Handover Authentication Scheme for EAP-Based Wireless Networks

    Extensible Authentication Protocol (EAP) is a framework which aims to provide a flexible authentication for wireless networks. Due to the involvement of an EAP server and several round trips between a Mobile Node (MN) and the EAP server, a full EAP authentication takes about 1000ms which is unacceptable in a...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Oct 2011

    Capacity-Aware Routing Using Throw-Boxes

    Deploying the static wireless devices (throw-boxes) at certain locations can help message dissemination among mobile nodes in delay tolerant networks. The mobile nodes traveling between throw-boxes form network links that carry the temporally stored messages at one box to another. However, the aggregated mobility between pairs of boxes reveals a...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Dec 2009

    Joint Medium Access Control, Routing and Energy Distribution in Multi-Hop Wireless Networks

    It is a challenging task for multi-hop wireless networks to support multimedia applications with Quality-of-Service (QoS) requirements. This letter presents a joint cross-layer optimization approach, i.e., joint medium access control, routing, and energy distribution. User satisfaction represented by user utility is maximized within the required network lifetime, given the constraints...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Dec 2009

    On the Design, Selection Algorithm and Performance Analysis of Limited Feedback Transmit Beamforming

    Multiple-Input Multiple-Output (MIMO) systems achieve significant diversity and array gains by using transmit beamforming. When complete Channel State Information (CSI) is not available at the transmitter, a common set of beamformers (codebook) is used by both the transmitter and the receiver. For each channel realization, the best beamformer is selected...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Dec 2009

    Physical Layer Differential Network Coding for Two-Way Relay Channels

    In this paper, the authors consider differential modulation in Two-Way Relay Channels (TWRC). In single antenna systems, the authors propose non-coherent schemes for both Amplify- and Forward (AF) and Decode-and-Forward (DF) where the channel state information is not required. These new schemes are counterparts of the traditional non-coherent detection in...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Dec 2009

    Improved OFDMA Uplink Transmission Via Cooperation in the Presence of Frequency Offsets

    In this paper, the authors evaluate the performance improvement in an Orthogonal Frequency-Division Multiple Access (OFDMA) uplink achievable with cooperative relaying in the presence of frequency offsets. The authors consider both the Amplify-and-Forward (AF) and Decode-and-Forward (DF) relays. In each transmission, each node plays two roles i.e., the source node...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Dec 2009

    Reduced Complexity ML Detection for Differential Unitary Space-Time Modulation With Carrier Frequency Offset

    Recently, a Maximum Likelihood (ML) detection rule for Differential Unitary Space Time Modulation (DUSTM) under the existence of unknown Carrier Frequency Offset (CFO) has been derived. However, the ML detection is based on the exhaustive search over all the unitary group codes. In this paper, the authors design an efficient...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Dec 2009

    Cooperative OFDM Channel Estimation With Frequency Offsets

    Optimal channel estimation in a cooperative AF or DF OFDM in the presence of frequency offsets has been considered. For a given channel order L, the spatial diversity gain was much easier to obtain in the DF mode than in the AF mode. The PEP performance of an orthogonal space-time...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Dec 2009

    Optimal Pilots for Frequency Offset and Channel Estimation in OFDMA Uplink

    Optimal pilots design and placement for the frequency offset and channel estimation in Orthogonal Frequency Division Multiplexing Access (OFDMA) uplink systems are proposed. The received pilots of multiple users can always be demodulated, even if they are totally overlapped due to the large frequency offsets. With the knowledge of Channel...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Dec 2009

    Power Allocation in Wireless Relay Networks: A Geometric Programming-Based Approach

    In this paper, the authors consider an Amplify-and-Forward (AF) wireless relay system where multiple source nodes communicate with their corresponding destination nodes with the help of relay nodes. While each user is assisted by one relay, one relay can assist many users. Conventionally, each relay node is assumed to equally...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Dec 2009

    On the Eigenvalue Distribution of Correlated MIMO Channels by Character Expansion of Groups

    Multiple-Input Multiple-Output (MIMO) channels have been studied from various aspects including the average of the mutual information between the transmitter and receiver (ergodic capacity) when the channel gains are known to the receiver only. A common approach for capacity analysis is to find the Moment Generating Function (MGF) of the...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Dec 2009

    Maximum Likelihood Detection for Differential Unitary Space-Time Modulation With Carrier Frequency Offset

    Can conventional Differential Unitary Space Time Modulation (DUSTM) be applied when there is an unknown Carrier Frequency Offset (CFO)? This paper answers this question affirmatively and derives the necessary Maximum Likelihood (ML) detection rule. The asymptotic performance of the proposed ML rule is analyzed, leading to a code design criterion...

    Provided By Institute of Electrical and Electronics Engineers

  • White Papers // Mar 2010

    On the Interplay of Parallelization, Program Performance, and Energy Consumption

    This paper derives simple, yet fundamental formulas to describe the interplay between parallelism of an application, program performance, and energy consumption. Given the ratio of serial and parallel portions in an application and the number of processors, the authors derive optimal frequencies allocated to the serial and parallel regions in...

    Provided By Institute of Electrical and Electronics Engineers