Hindawi Publishing

Displaying 361-400 of 1693 results

  • White Papers // Jun 2010

    Simulation of 802.21 Handovers Using ns-2

    The new IEEE 802.21 standard specifies link layer intelligence and other related network information to upper layers in order to optimize handovers between networks of different types, such as WiMAX, Wi-Fi, and 3GPP. This paper makes a short description of 802.21 standard, how it is implemented in ns-2, and the...

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  • White Papers // Mar 2010

    A Novel Prioritization Scheme to Improve QoS in IEEE 802.11e Networks

    IEEE 802.11 WLAN utilizes a distributed function at its MAC layer, namely, DCF to access the wireless medium. Due to its distributed nature, DCF is able to guarantee working stability in a wireless medium while maintaining the assembling and maintenance cost in a low level. However, DCF is inefficient in...

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  • White Papers // Dec 2009

    WiFi and WiMAX Secure Deployments

    Wireless Broadband offers incredibly fast, "Always on" Internet similar to ADSL and sets the user free from the fixed access areas. In order to achieve these features standardisation was achieved for Wireless LAN (WLANs) and Wireless Metropolitan Area Networks (WMANs) with the advent of IEEE802.11 and IEEE802.16 family of standards,...

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  • White Papers // Oct 2012

    Mobile Base Station and Clustering to Maximize Network Lifetime in Wireless Sensor Networks

    Using a mobile Base Station (BS) in a wireless sensor network can alleviate non-uniform energy consumption among sensor nodes and accommodate partitioned networks. In the work of Jerew and Liang (2009), the authors have proposed a novel clustering-based heuristic algorithm for finding a trajectory of the mobile BS that strikes...

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  • White Papers // Oct 2012

    Changing Trends in Modeling Mobility

    A phenomenal increase in the number of wireless devices has led to the evolution of several interesting and challenging research problems in opportunistic networks. For example, the random waypoint mobility model, an early, popular effort to model mobility, involves generating random movement patterns. Previous research efforts, however, validate that movement...

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  • White Papers // Sep 2012

    Evolutionary Game Theory-Based Collaborative Sensing Model in Emergency CRAHNs

    Game theory has been a tool of choice for modeling dynamic interactions between autonomous systems. Cognitive Radio Ad Hoc Networks (CRAHNs) constituted of autonomous wireless nodes are a natural fit for game theory-based modeling. The game theory-based model is particularly suitable for "Collaborative spectrum sensing" where each cognitive radio senses...

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  • White Papers // Oct 2012

    Improved Maximum Likelihood S-FSK Receiver for PLC Modem in AMR

    This paper deals with an optimized software implementation of a narrowband power line modem. The modem is a node in Automatic Meter Reading (AMR) system compliant to IEC 61334-5-1 profile and operates in the CENELEC-A band. Because of the hostile communication environments of power line channel, a new design approach...

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  • White Papers // Jun 2012

    On Asymptotic Analysis of Packet and Wormhole Switched Routing Algorithm for Application-Specific Networks-on-Chip

    Parallel Processing refers to the concept of speeding-up the execution of a program by dividing the program into multiple fragments that can execute simultaneously, each on its own processor. A program being executed across n processors might execute n times faster than it would use a single processor. It is...

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  • White Papers // Aug 2012

    A Semiparametric Model for Hyperspectral Anomaly Detection

    Using Hyper-Spectral (HS) technology, this paper introduces an autonomous scene anomaly detection approach based on the asymptotic behavior of a semi-parametric model under a multisampling testing and minimum-order statistic scheme. Scene anomaly detection has a wide range of use in remote sensing applications, requiring no specific material signatures. Uniqueness of...

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  • White Papers // Sep 2012

    No-Reference Stereoscopic IQA Approach: from Nonlinear Effect to Parallax Compensation

    Three-Dimensional (3D) imaging has been an extensive research area, the application of which ranges from entertainment, such as videos and games, to specialized domains, such as education and medicine. As more and more image processing operations have been specifically designed for stereoscopic images, the necessity for an effective perceptual stereoscopic...

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  • White Papers // Sep 2012

    Performance Analysis of Different Types of Sensor Networks for Cognitive Radios

    Cognitive Radio (CR) is a potential technology for increasing spectral efficiency in wireless communications systems. In a cognitive radio system, secondary users temporarily use spectrum that is not utilized, as long as negligible impact is caused to primary licensed users. In order to opportunistically access temporarily unused spectrum, the spectrum...

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  • White Papers // Sep 2012

    Video Compression Schemes Using Edge Feature on Wireless Video Sensor Networks

    A Wireless Video Sensor Network (WVSN) is a special kind of Wireless Sensor Network (WSN) that is capable of capturing video data at video sensor nodes (nodes have the equipment to capture video data), processing the data, and transferring them using a multihop technique to the base station. Two types...

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  • White Papers // Sep 2012

    Location-Aware Source Routing Protocol for Underwater Acoustic Networks of AUVs

    Acoustic networks of Autonomous Underwater Vehicles (AUVs) cannot typically rely on protocols intended for terrestrial radio networks. This paper describes a new Location-Aware Source Routing (LASR) protocol shown to provide superior network performance over two commonly used network protocols - flooding and Dynamic Source Routing (DSR) - in simulation studies...

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  • White Papers // Apr 2012

    ARQ Protocols for Two-Way Wireless Relay Systems: Design and Performance Analysis

    In this paper, the authors focus on the designing of Automatic Repeat-reQuest (ARQ) protocols for the two-way wireless relay systems. According to different feedback schedules, they propose three basic ARQ protocols to improve the throughput of two-way relay systems, namely, Relay-only ARQ (Ro-ARQ), Terminal-only ARQ (To-ARQ) and Relay-Terminal ARQ (RT-ARQ)....

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  • White Papers // Jul 2012

    Prevention and Detection Methods for Enhancing Security in an RFID System

    Low-cost Radio Frequency IDentification (RFID) tag is exposed to various security and privacy threats due to computational constraint. This paper proposes the use of both prevention and detection techniques to solve the security and privacy issues. A mutual authentication protocol with integration of tag's unique electronic fingerprint is proposed to...

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  • White Papers // Jul 2012

    Multilayer Orthogonal Beamforming for Priority-Guaranteed Wireless Communications

    To utilize the benefits of cellular systems, wireless Machine-To-Machine (M2M) communications over cellular systems are being widely considered. In order to support efficient spectrum sharing between M2M devices and normal mobile users, in this paper, the authors propose a Multilayer Orthogonal BeamForming (MOBF) scheme forM2M communications over Orthogonal Frequency Division...

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  • White Papers // Jun 2012

    Investigation of Uncoordinated Coexisting IEEE 802.15.4 Networks with Sleep Mode for Machine-To-Machine Communications

    The low-energy consumption of IEEE 802.15.4 networks makes it a strong candidate for Machine-To-Machine (M2M) communications. As multipleM2M applications with 802.15.4 networks may be deployed closely and independently in residential or enterprise areas, supporting reliable and timely M2M communications can be a big challenge especially when potential hidden terminals appear....

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  • White Papers // Mar 2012

    Improved Virtual Potential Field Algorithm Based on Probability Model in Three-Dimensional Directional Sensor Networks

    In conventional directional sensor networks, coverage control for each sensor is based on a 2D directional sensing model. However, 2D directional sensing model failed to accurately characterize the actual application scene of image/video sensor networks. To remedy this deficiency, the authors propose a 3D directional sensor coverage-control model with tunable...

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  • White Papers // Mar 2012

    K-Coverage Persevering Routing Technique Based on Event Occurrence Patterns for Wireless Sensor Networks

    In this paper, the authors propose a new routing algorithm schema based on event occurrence history to secure K-Coverage of event paths and maintain the maximum degree of coverage. In the proposed method the nodes located around event path try to save their battery power by not participating in data...

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  • White Papers // Mar 2012

    CAC-MAC: A Cross-Layer Adaptive Cooperative MAC for Wireless Ad Hoc Networks

    Cooperative communication has been recently proposed as a way to mitigate fading in wireless networks. A Cross-layer Adaptive Cooperative MAC (CAC-MAC) protocol for IEEE 802.11 DCF-based wireless ad hoc networks is proposed. The novel aspect and core idea of the authors' proposal is a cross-layer adaptive data transmission algorithm considering...

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  • White Papers // Feb 2012

    Low-Cost Monitoring and Intruders Detection Using Wireless Video Sensor Networks

    In this paper, the authors' aim is to prolong the whole network lifetime while fulfilling the surveillance application needs. They present a novel scheduling algorithm where only a subset of video nodes contributes significantly to detect intruders and prevent malicious attacker to predict the behavior of the network prior to...

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  • White Papers // Feb 2012

    Time-Independent Data Collection Protocol in Mobility-Assistant Wireless Sensor Networks with Duty Cycles

    Mobility-assistant sensor networks comprise mobile elements, and static sensors are established for the purpose of solving the serious problems such as overlapping or energy holes in Wireless Sensor Networks (WSNs). In this paper, the authors first study on the MS discovery mechanism and the factors which affect the efficiency of...

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  • White Papers // Feb 2012

    Design and Implementation of Enhanced Surveillance Platform with Low-Power Wireless Audio Sensor Network

    Video surveillance system, which can provide real-time display of the monitored scene and video playback, has been employed in many areas including commercial security, accident investigation, law enforcement, and emergency response. This paper describes the platform architecture, including design, implementation, and performance. The authors describe the hardware and software components...

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  • White Papers // Feb 2012

    A Mobile Agent Routing Algorithm in Dual-Channel Wireless Sensor Network

    A Mobile Agent Routing Algorithm (MARA) is presented in this paper, and then based on the dual-channel communication model, the two-layer network combination optimization strategy is also proposed. Since this strategy deals with the collision between packets and the multicast suppression in channel competitive process well, the blocking probability of...

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  • White Papers // Jan 2012

    A Network Coding Based Rarest-First Packet Recovery Algorithm for Transmitting Geocast Packets Over Hybrid Sensor-Vehicular Networks

    Vehicular Ad hoc NETwork (VANET) and road-side sensors are used to improve driving safety in many applications. Sensor nodes deployed along the roadside are used to sense road conditions and then deliver information about dangerous conditions to vehicles. In hybrid sensor-vehicular networks, new challenges arise and should be addressed. Network...

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  • White Papers // Feb 2012

    An Extended Virtual Force-Based Approach to Distributed Self-Deployment in Mobile Sensor Networks

    Wireless sensor networks can be deployed manually or spread randomly over the interested regions for practical applications. However, in many working environments, such as remote harsh fields, disaster areas, and toxic gas regions, it is almost impossible to deploy sensors by human beings. In such case, deploying the sensor nodes...

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  • White Papers // Feb 2012

    A Local World Evolving Model for Energy-Constrained Wireless Sensor Networks

    In this paper, the authors aim at improving the interactions among sensor nodes, and they present a heterogeneous local-world model to form large-scale wireless sensor networks based on complex network theory. Two types of nodes, normal nodes and cluster nodes are added to the networks. The degree distribution for this...

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  • White Papers // Feb 2012

    Rendezvous Data Collection Using a Mobile Element in Heterogeneous Sensor Networks

    Since the emergence, Wireless Sensor Networks (WSNs) undertake intensive data collection during the sensing period. However, the limited energy storage of tiny sensors involved in a WSN harshly confines their ability of transmitting the acquired data. As a result, the premature death of several sensors always perturbs the connectivity of...

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  • White Papers // Feb 2012

    Dynamic Key-Updating: Privacy-Preserving Authentication for RFID Systems

    The objective of private authentication for Radio Frequency IDentification (RFID) systems is to allow valid readers to explicitly authenticate their dominated tags without leaking the private information of tags. In previous designs, the RFID tags issue encrypted authentication messages to the RFID reader, and the reader searches the key space...

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  • White Papers // Feb 2012

    Improving Accuracy for 3D RFID Localization

    Radio Frequency IDentification (RFID) becomes a prevalent labeling and localizing technique in the recent years. Deploying indoor RFID localization systems facilitates many applications. Previous approaches, however, are most based on 2D design and cannot provide 3D location information. The lack of one-dimensional information may lead 2D-based systems to inaccurate localization....

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  • White Papers // Feb 2012

    Pervasive Smart Spaces and Environments: A Service-Oriented Middleware Architecture for Wireless Ad Hoc and Sensor Networks

    In the twenty-first century, the impact of wireless and ubiquitous technologies is changing the way people perceive and interact with the physical world. These communication paradigms promise to change and redefine, in a reasonably short period of time, the most common way of the people everyday living. The continuous advances...

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  • White Papers // Jan 2012

    Anchor-Node-Based Distributed Localization with Error Correction in Wireless Sensor Networks

    Many applications of wireless sensor networks such as object tracking, environment and habitat monitoring, intrusion detection, and geographic routing rely on the location information of sensor nodes. To provide accurate position information of sensor nodes, each sensor node can be equipped with GPS. In many applications, however, it is not...

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  • White Papers // Feb 2012

    On Optimal Antijamming Strategies in Sensor Networks

    Physical layer radio jamming is a serious security threat to a wireless sensor network since the network relies on open wireless radio channels. A radio jammer is typically strategic and chooses its jamming strategy in response to the possible defense strategy taken by the sensor network. In this paper, the...

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  • White Papers // Feb 2012

    Traffic Rerouting Strategy Against Jamming Attacks in WSNs for Microgrid

    In a micro-grid as an energy infrastructure, the vulnerability against jamming attacks is fatal. Thus, the ability to deal with jamming attacks and maintain an acceptable level of service degradation in presence of the attacks is needed. To solve the problem, the authors propose a traffic rerouting scheme in wireless...

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  • White Papers // Jan 2012

    Enhancing Sink-Location Privacy in Wireless Sensor Networks Through K -Anonymity

    Due to the shared nature of wireless communication media, a powerful adversary can eavesdrop on the entire radio communication in the network and obtain the contextual communication statistics, for example, traffic volumes, transmitter locations, and so forth. To protect the sink-location privacy from a powerful adversary with a global view,...

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  • White Papers // Jan 2012

    A Distributed Reclustering Hierarchy Routing Protocol Using Social Welfare in Wireless Sensor Networks

    Wireless Sensor Networks (WSNs) are capable of sensing physical or environmental conditions, such as motion, pressure, and images of the environment, as well as seismic, electromagnetic, and acoustic waves. Sensor nodes form an ad hoc network within the target field, routing data packets to a specified center(s). For example, sensors...

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  • White Papers // Jan 2012

    InContexto: Multisensor Architecture to Obtain People Context from Smartphones

    The way users interact with Smartphones is changing after the improvements made in their embedded sensors. Increasingly, these devices are being employed as tools to observe individuals habits. Smartphones provide a great set of embedded sensors, such as accelerometer, digital compass, gyroscope, GPS, microphone, and camera. This paper aims to...

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  • White Papers // Jan 2012

    Energy-Efficient Secure Path Algorithm for Wireless Sensor Networks

    To collect the data and transmit them on the base station is the main task of the sensor nodes in Wireless Sensor Networks (WSNs). This transmission requires a specific routing algorithm. To prolong the network lifetime, sensor nodes need a secure load-balancing route. In this paper, the authors investigate the...

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  • White Papers // Feb 2012

    Energy Efficient MAC Protocol for Low-Energy Critical Infrastructure Monitoring Networks Using Wakeup Radio

    Critical infrastructure monitoring applications are rapidly increasing. Application requirements include reliable data transfer, energy efficiency, and long deployment lifetime. In this paper, the authors present a Medium Access Control (MAC) protocol for Low-Energy Critical Infrastructure Monitoring (LECIM) applications. The proposed MAC protocol is based on a framed slotted aloha multiple...

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  • White Papers // Dec 2011

    Logic Macroprogramming for Wireless Sensor Networks

    It is notoriously difficult and tedious to program Wireless Sensor Networks (WSNs). To simplify WSN programming, the authors propose Sense2P, a logic macro-programming system for abstracting, programming, and using WSNs as globally deductive databases. Unlike macro-programs in previous works, their logic macro-programs can be described declaratively and imperatively. In Sense2P,...

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