ICST

Displaying 201-240 of 255 results

  • White Papers // May 2011

    Network Calculus: Application to Switched Real-Time Networking

    In this paper, the authors show how Network Calculus can be used to determine whether a switched network may satisfy the time constraints of a real-time application. If switched architecture are interesting in the sense that they offer flexible design and may eliminate collisions in Ethernet-based net-work, they are not...

    Provided By ICST

  • White Papers // May 2011

    Physical Layer Authentication Over an OFDM Fading Wiretap Channel

    Precise channel estimation at the physical layer allows to authenticate the source of a message in a wireless environment without the need of a pre-shared secret key based on the rapid spatial decorrelation of the channel. The authors consider the authentication scheme proposed by Xiao et al. and modify to...

    Provided By ICST

  • White Papers // May 2011

    Secure Distributed Lossless Compression With Side Information at the Eavesdropper

    This paper investigates the problem of secure distributed lossless compression in the presence of arbitrarily correlated side information at an eavesdropper. This scenario consists of two encoders (referred to as Alice and Charlie) that wish to reliably transmit their respective (correlated) sources to a legitimate receiver (referred to as Bob)...

    Provided By ICST

  • White Papers // May 2011

    The Jamming Game in an OFDM Setting

    Orthogonal Frequency Division Multiplexing (OFDM) has been chosen as the physical layer solution for a large variety of emerging and future wireless networks, due to its robustness in coping with frequency selective channels and efficient transceiver implementation. Its adoption in the transmission architecture should therefore be properly taken into account...

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  • White Papers // May 2011

    Relay and Jammer Cooperation as a Coalitional Game in Secure Cooperative Wireless Networks

    In this paper, the authors investigate cooperation of conventional relays and friendly jammers subject to secrecy constraints for cooperative networks. In order to obtain an optimized secrecy rate, the source selects several conventional relays and friendly jammers from the intermediate nodes to assist data transmission, and in return, it needs...

    Provided By ICST

  • White Papers // May 2011

    Power Allocation in Team Jamming Games in Wireless Ad Hoc Networks

    In this paper, the authors study the problem of power allocation in teams. Each team consists of two agents who try to split their available power between the tasks of communication and jamming the nodes of the other team. The agents have constraints on their total energy and instantaneous power...

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  • White Papers // May 2011

    Low Complexity Resource Allocation for OFDMA Based on Coalitional Game Theory

    This paper investigates a fair adaptive resource management criterion (in terms of transmit powers and sub-channel assignment) for the uplink of an Orthogonal Frequency Division Multiple Access (OFDMA) network, populated by mobile users with constraints in terms of target data rates. The inherent optimization problem is tackled with the analytical...

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  • White Papers // May 2011

    Universal Linear Pricing for Multiple Access and Broadcast Channels Under QoS Requirements

    In this paper, the authors address the problem of power allocation in Multiple Access Channels (MAC) and Broadcast Channels (BC) with linear pricing framework to ensure that each user in the interference network can achieve its utility requirement. In the framework the system optimizer maximizes the system utility with the...

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  • White Papers // May 2011

    Adversarial Behavior in Network Mechanism Design

    This paper studies the effects of and countermeasures against adversarial behavior in network resource allocation mechanisms such as pricing and auctions. It models the heterogeneous behavior of users, which ranges from altruistic to selfish and even to malicious, using game theory. The paper adopts a mechanism design approach to quantify...

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  • White Papers // May 2011

    Mean Field Stochastic Games for SINR-Based Medium Access Control

    In this paper, the authors study medium access control with interference management. They formulate a SINR-based dynamic channel access as a stochastic game in which the players adapt their retransmission scheme based on their own backoff state. They analyze the asymptotics of the system using mean field dynamics. Both stable...

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  • White Papers // May 2011

    Graph-Based Coalitional Games - An Analysis Via Characteristics

    In this paper, the authors motivate a new approach to analyze the computational complexity of solution concepts and player-based properties, as well as other properties of coalitional games. This approach is based on the idea to abstract away from detailed game representations to analyze games via standard complexity proofs, towards...

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  • White Papers // May 2011

    The Price of Re-Establishing Perfect, Almost Perfect or Public Monitoring in Games With Arbitrary Monitoring

    This paper establishes a connection between the notion of observation (or monitoring) structure in game theory and the one of communication channels in Shannon theory. One of the objectives is to know under which conditions an arbitrary monitoring structure can be transformed into a more pertinent monitoring structure. To this...

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  • White Papers // May 2011

    Coopetition - Practical Methodology for Efficient Sharing of Radio Resources in Wireless Networks

    In this paper, the authors present the idea of resource allocation using the coopetition methodology, which combines the advantages of both cooperative and competitive approaches. This idea is known from economics, as well as in some other fields, e.g., in the complex production and management systems. They show that the...

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  • White Papers // May 2011

    Routing Games in the Many Players Regime

    The paper has established the convergence of the Nash equilibrium in routing games to the Wardrop equilibrium as the number of players grows. The result was obtained under diagonal strict convexity assumption. The authors extend this result and establish the convergence under weaker convexity assumptions (the B type cost structure)....

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  • White Papers // May 2011

    Achievable Secrecy Rates for Wiretap OFDM With QAM Constellations

    Orthogonal Frequency Division Multiplexing (OFDM) systems have enjoyed widespread adoption as the physical layer standard for high data rate wired and wireless networks, due to their ability to efficiently cope with slowly varying dispersive channels. Therefore in searching for feasible implementations of physical layer security techniques, it is appropriate to...

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  • White Papers // May 2011

    On the Multi-Antenna Wiretap Channel With Delayed CSI at the Transmitter

    The Multi-Input Single-Output (MISO) Gaussian wiretap channel with delayed Channel State Information (CSI) available at the transmitter and at the eavesdropper is investigated. This scenario may occur when the legitimate receiver sends its channel state to the transmitter via a delayed feedback link which can be also overheard by an...

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  • White Papers // May 2011

    MAC With Partially Cooperating Encoders and Security Constraints

    The authors study a special case of Willems's two-user multiaccess channel with partially cooperating encoders from security perspective. This model differs from Willems's setup in that only one encoder, Encoder 1, is allowed to conference, Encoder 2 does not transmit any message, and there is an additional passive eavesdropper from...

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  • White Papers // Mar 2011

    A Site-Specific Indoor Link Model for Realistic Wireless Network Simulations

    Compared to testbeds, the efficiency and accuracy of wireless networking simulations are constantly questioned by the network community. It is widely accepted today that the current network simulators are not able to fully represent the real wireless characteristics, especially at the PHYsical (PHY) layer. This affects the trustability of simulation-based...

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  • White Papers // Sep 2010

    Performance of Deterministic Local Sensing Aggregation Under Interference

    In this paper, the authors evaluate the delay and sensing performance of distributed cooperative sensing in wireless sensor networks assisting cognitive secondary operation. They propose a time division multiple access protocol to exchange sensing information among neighboring sensors, that is tunable in terms of sensing cooperation range and frequency reuse...

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  • White Papers // Sep 2010

    Blind Standard Identification With Bandwidth Shape and GI Recognition Using USRP Platforms and SDR4all Tools

    In this paper, focusing on identifying standards blindly, the authors propose a bandwidth shape sensor and a GI (guard interval) sensor using USRP (Universal Software Radio Peripheral) platforms and SDR4all tools. These sensors are fundamental parts of the so-called Blind Standard Recognition Sensor. The blind standard bandwidth sensor is based...

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  • White Papers // Sep 2010

    Standard Recognising Self Organizing Map Based Cognitive Radio Transceiver

    Cognitive Radio (CR) Systems have transceivers with the ability to adjust their operating parameters after observing the results in order to decide to operate in a specific radio configuration, expecting to move the radio towards some optimized operational state. Framed within this statement, this paper introduces and evaluates the use...

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  • White Papers // Sep 2010

    Multiple Description Source Coding for Cognitive Radio Systems

    Multiple Description Coding (MDC) is applied for delay-sensitive data traffic to alleviate interruptions caused by primary users in cognitive radio systems. For Gaussian source, a simplified algorithm for the exhaustive search of optimal distortions and rates is proposed based on the achievable region of coding rates and delay requirement. For...

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  • White Papers // Sep 2010

    SINR Balancing in the Downlink of Cognitive Radio Networks With Imperfect Channel Knowledge

    In this paper, the authors consider the problem of Signal-to-Interference-plus-Noise Ratio (SINR) balancing in the downlink of Cognitive Radio (CR) networks while simultaneously keeping interference levels at Primary User (PU) Receivers (RXs) below an acceptable threshold with uncertain channel state information available at the CR Base-Station (BS). They optimize the...

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  • White Papers // Sep 2010

    Supporting Proactive Application Event Notification to Improve Sensor Network Performance

    As wireless sensor networks gain in popularity, many deployments are posing new challenges due to their diverse topologies and resource constraints. Previous work has shown the advantage of adapting protocols based on current network conditions (e.g., link status, neighbor status), in order to provide the best service in data transport....

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  • White Papers // Jul 2010

    Contention Vs. Polling: A Study in Body Area Networks MAC Design

    Medium Access Control design for Body Area Networks is challenging due to the uniqueness of the wireless channel characteristics (highly variable in time) and the need for ultra low power while maintaining reasonable performance. Using the authors temporal BAN channel models they study trade-offs created by a mix of two...

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  • White Papers // Apr 2010

    Broadcast Video Streaming in Cellular Networks: An Adaptation Framework for Channel, Video and AL-FEC Rates Allocation

    Video streaming is one of the most important applications that will make use of the high data rates offered by 4G networks. The current video transport techniques are already very advanced, and the more immediate problems lie in the joint optimization of video coding, AL-FEC, and PHY rate selection with...

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  • White Papers // Mar 2010

    A Comprehensive MIPv6 Based Mobility Management Simulation Engine for the Next Generation Network

    Mobility management is one of the core requirements of the IPv6 based NGN to provide seamless handover services to mobile entities. In this regard, IETF has proposed protocols like Mobile IPv6 (MIPv6), FastMIPv6 (FMIPv6) and HierarchicalMIPv6 (HMIPv6) to provide efficient mobility services. Due to the lack of deployment, there is...

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  • White Papers // Mar 2010

    Integration of a GIST Implementation Into OMNeT++

    The General Internet Signaling Transport (GIST) protocol was specified by the IETF in order to provide a generic transport protocol for signaling messages. A group at the Institute of Telematics implemented the GIST protocol and evaluated it already in smaller testbed setups. An evaluation of GIST in large-scale scenarios can,...

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  • White Papers // Mar 2010

    Validation of the IEEE 802.11 MAC Model in the Ns3 Simulator Using the EXTREME Testbed

    The authors validate the IEEE 802.11 MAC layer model in ns3 by means of measurements on the EXTREME testbed. They consider different scenarios: communications within a single pair of nodes, multi-user communications using either VoIP or saturated traffic, and communications in the presence of hidden nodes. For each scenario, they...

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  • White Papers // Mar 2010

    Evaluation of IMT-Advanced Scenarios Using the Open Wireless Network Simulator

    With the commence of the IMT-Advanced (IMT-A) submission and evaluation process, the vague term "4th generation wireless networks" moves towards existing standards, technologies and hardware. A significant part of the evaluation process is based on the system level simulation of reference scenarios. In this paper, the authors present how the...

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  • White Papers // Mar 2010

    Consistency Management for Interactive Peer-to-Peer-Based Systems

    Consistency is a crucial requirement for Massively Multiuser Virtual Environments (MMVEs). Such systems provide virtual worlds in which thousands of users can interact in real-time. To realize a consistent world view for all users, a flexible consistency management is required which balances the responsiveness and the level of consistency in...

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  • White Papers // Oct 2009

    Towards Comparable Simulations of Cooperating Objects and Wireless Sensor Networks

    Simulators are indispensable tools to support the development and testing of cooperating objects such as Wireless Sensor Networks (WSN). However, it is often not possible to compare the results of different simulation tools. Thus, the goal of this paper is the specification of a generic simulation platform for cooperating objects....

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  • White Papers // Oct 2009

    Simulation Modeling of Secure Wireless Sensor Networks

    This paper describes an extensible simulation environment for the modeling of Wireless Sensor Networks (WSNs). In particular, their simulator facilitates the study of secure connectivity between sensor nodes. The simulator has five main components: network topology model, key establishment protocol, adversary model for node capture, network analysis tools, and a...

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  • White Papers // Oct 2009

    Estimating Service Resource Consumption From Response Time Measurements

    The authors propose a linear regression method and a maximum likelihood technique for estimating the service demands of requests based on measurement of their response times instead of their CPU utilization. Their approach does not require server instrumentation or sampling, thus simplifying the parameterization of performance models. The benefit of...

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  • White Papers // Oct 2009

    Using Bulk Arrivals to Model I/O Request Response Time Distributions in Zoned Disks and RAID systems

    Useful analytical models of storage system performance must support the characteristics exhibited by real I/O workloads. Two essential features are the ability to cater for bursty arrival streams and to support a given distribution of I/O request size. This paper develops and applies the theory of bulk arrivals in queuing...

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  • White Papers // Oct 2009

    Automated Extraction of Palladio Component Models From Running Enterprise Java Applications

    Nowadays, software systems have to fulfill increasingly stringent requirements for performance and scalability. To ensure that a system meets its performance requirements during operation, the ability to predict its performance under different configurations and workloads is essential. Most performance analysis tools currently used in industry focus on monitoring the current...

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  • White Papers // May 2009

    M-TEEVE: Real-Time 3D Video Interaction and Broadcasting Framework for Mobile Devices

    3D video is an emerging technology that promises immersive experiences in a truly seamless environment. This paper presents a new proxy-based framework to extend the 3D video experience to mobile devices. The framework has two major features. First, it allows audience to use mobile devices to change rendering viewpoints and...

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  • White Papers // May 2009

    Samera:A Scalable and Memory-Efficient Feature Extraction Algorithm for Short 3D Video Segments

    Tele-immersive systems, are growing in popularity and sophistication. They generate 3D video content in large scale, yielding challenges for executing data-mining tasks. Some of the tasks include classification of actions, recognizing and learning actor movements and so on. Fundamentally, these tasks require tagging and identifying of the features present in...

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  • White Papers // Apr 2009

    Challenges of Implementing Cyber-Physical Security Solutions in Body Area Networks

    Cyber-physical approach to securing Body Area Networks (BANs) provides solutions that are plug-n-play and trans-parent to its users. These Cyber-Physical Security Solutions (CPSS) actively involve characteristics from the physical environment. As a result they require a combination of signal processing (To extract features from the physical environment) and security primitives...

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  • White Papers // Jan 2009

    Efficient Cross-Layer Simulator for Performance Evaluation of Wireless Mesh Networks

    Wireless Mesh Networks (WMNs) are emerging as a promising technology for backhauling data traffic from wireless access networks to the wired Internet that expected to support various types of applications with different Quality of Service (QoS) requirements. While wireless mesh networking has attracted great industrial and academic interest, many research...

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  • White Papers // Jun 2012

    Cognitive Radios With Ergodic Capacity Guarantees for Primary Users

    Cognitive radios implement adaptive resource allocation schemes that exploit knowledge of the channel state information to optimize the performance of the secondary users while limiting the interference to the primary users. The algorithms in this paper are designed to maximize the weighted sum-rate of secondary users which transmit orthogonally and...

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  • White Papers // Jun 2012

    Opportunistic Spectrum Access in Cognitive Radio Based on Channel Switching

    This paper investigates the performance of a cognitive radio transceiver that can monitor multiple channels and opportunistically use any one of them should it be available. In the authors' work, they propose and compare two different opportunistic channel access schemes. The first scheme applies when the Secondary User (SU) has...

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  • White Papers // Sep 2011

    Sensing Order Dispersion for Autonomous Cognitive Radios

    When autonomous Cognitive Radios (CRs) have to search multiple potential channels for spectrum opportunities, they face competition from one another to access the channel. The end result of this competition is reduced CR throughput due to collisions among CRs that transmit in the same channel. In this context, the channel...

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  • White Papers // Sep 2011

    Sparse Signal Sensing With Non-Uniform Undersampling and Frequency Excision

    The authors propose a novel compressive sensing algorithm for cognitive radio networks, based on non-uniform under-sampling. It is known that the spectrum of uniformly under-sampled signals exhibit frequency aliasing, whereby the frequency location is impossible. To alleviate aliasing, non-uniform sampling can be used. This, however, generates a high level of...

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  • White Papers // Sep 2011

    An Algorithm for Fast REM Construction

    The Radio Environment Map (REM) stores radio environmental information that can be used to enhance cognitive radio resource management in wireless networks. In this paper, the authors propose an iterative REM building process based on Kriging interpolation technique that builds the REM using geo-located measurements performed by mobile terminals. As...

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  • White Papers // Sep 2011

    A Low-Interference Relay Selection for Decode-and-Forward Cooperative Network in Underlay Cognitive Radio

    In the underlay Decode-and-Forward (DaF) cooperative Cognitive Radio (CR) network, an optimal relay can be selected by the conventional max-min selection on the condition of not violating the Interference Temperature (IT) limit. However, the max-min selection may cause some extra amount of interference to the Primary System (PS) such that...

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  • White Papers // Sep 2011

    Self-Enforcement Strategy for Energy-Efficient Relaying in Wireless Ad-Hoc Networks

    In this paper, the authors propose and examine 802.11b-based MAC protocol for wireless ad-hoc relay networks. The objective of the proposed protocol is to incorporate self-enforcing strategy to achieve energy efficiency in function of joules required for providing data transmission between end users. Regarding energy requirements for transmitting and receiving...

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  • White Papers // Sep 2011

    Exploiting Spatial Dimension in Cognitive Radios and Networks

    This paper studies the maximum number of users that can be allocated in the same frequency band in case of using beamforming in a transmitter and a receiver by simulations. With the use of smart antennas the spectrum can be used efficiently, and at the same time the Quality of...

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  • White Papers // Sep 2011

    The Capacity of Cognitive Ad-Hoc Networks With Carrier Sensing Errors

    The authors analyze the capacity of cognitive ad-hoc networks under the effects of sensing errors: false alarm and missed detection. They present an ad-hoc network model overlaid on a primary system from which a cognitive node exploits spectrum holes for retransmissions. They derive per-link capacity, the indicator of the network's...

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  • White Papers // Sep 2011

    The Sum Capacity of Underlay Cognitive Broadcast Channel

    The authors study the sum capacity of the underlay cognitive BroadCast (BC) channel with M Primary Receivers (PRs) and K Secondary Receivers (SRs). In particular, the sum capacity is investigated under an average Transmit Power Constraint (TPC) on the SRs and multiple average or peak Interference Power Constraints (IPCs) on...

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  • White Papers // Sep 2011

    Network Scale Control for Distributed Networks by BER Analysis

    Node-to-node interference in the distributed networks comes to be one of the major challenges in recent wireless communication studies. The general methods make great improvement on such problem but influence the performances in other layer. It is because the models they based on, like SINR, barely consider the parameters across...

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  • White Papers // Jun 2011

    Stochastic-Geometric Model of Expected Service Area for Cognitive TV White Space Wireless Networks

    The authors address the problem of interference between cognitive wireless networks coexisting in the TV White Space (TVWS). They perform stochastic geometry analysis in order to evaluate the service area secondary cognitive devices can expect under mild to severe interference of neighboring networks. From their analysis, they foresee severe service...

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  • White Papers // May 2011

    Learning to Use the Spectrum in Self-Configuring Heterogenous Networks: A Logit Equilibrium Approach

    In this paper, the authors study the particular scenario where several transmitter-receiver pairs communicate subject to mutual interference due to the usage of the same frequency bands. In particular, they focus on the case of heterogeneous networks, where radio devices have different interests (utility functions), transmit configurations (sets of actions),...

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  • White Papers // May 2011

    Revenue Maximization in Spectrum Auction for Dynamic Spectrum Access

    In this paper, the authors consider the revenue maximization problem in auctions for dynamic spectrum access. They assume a frequency division method of spectrum sharing with a primary spectrum owner that can divide the available spectrum into sub-bands and sell them to secondary users. They assume that a secondary user's...

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  • White Papers // May 2011

    Modeling Network Coded TCP Throughput: A Simple Model and Its Validation

    The authors analyze the performance of TCP and TCP with Network Coding (TCP/NC) in lossy wireless networks. They build upon the simple framework introduced by Padhye et al. and characterize the throughput behavior of classical TCP as well as TCP/NC as a function of erasure rate, roundtrip time, maximum window...

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  • White Papers // May 2011

    A Symbolic Approach to Quantitative Analysis of Preemptive Real-Time Systems With Non-Markovian Temporal Parameters

    The method of stochastic state classes provides a means for quantitative analysis of a rather wide class of non-Markovian models. As a major and structural limitation, the approach cannot be applied to models encompassing a preemptive policy, which in the practice rules out the mechanism of suspension and resume usually...

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  • White Papers // Feb 2012

    Model For Sharing Femto Access

    In wireless access network optimization, today's main challenges reside in traffic offload and in the improvement of both capacity and coverage networks. The mobile operators are interested in solving their localized coverage and capacity problems in areas where the macro network signal is not able to serve the demand for...

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  • White Papers // May 2011

    Socially Optimal Pricing of Cloud Computing Resources

    The cloud computing paradigm offers easily accessible computing resources of variable size and capabilities. The authors consider a cloud-computing facility that provides simultaneous service to a heterogeneous, time-varying population of users, each associated with a distinct job. Both the completion time, as well as the user's utility, may depend on...

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  • White Papers // May 2011

    HASL: An Expressive Language for Statistical Verification of Stochastic Models

    The authors introduce the Hybrid Automata Stochastic Logic (HASL), a new temporal logic formalism for the verification of Discrete Event Stochastic Processes (DESP). HASL employs Linear Hybrid Automata (LHA) as machineries to select prefixes of relevant execution paths of a DESP. The advantage with LHA is that rather elaborate information...

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  • White Papers // May 2011

    On Distributed Power Control and Transceiver Optimization in Wireless Networks

    This paper outlines some recent results on the max-min SIR balancing problem in wireless networks in which power control and beamforming are the only mechanisms for resource allocation and interference management. In addition, the authors describe several potential extensions and improvements to existing algorithmic solutions, as well as prove the...

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  • White Papers // May 2011

    A Survey on YouTube Streaming Service

    Established in 2005, YouTube is one of the fastest-growing websites, and has become one of the most accessed sites in the Internet. It has a significant impact on the Internet traffic distribution, but itself is suffering from severe scalability constraints and quality of service. Understanding the features of YouTube is...

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  • White Papers // May 2011

    Network Calculus: Application to Switched Real-Time Networking

    In this paper, the authors show how Network Calculus can be used to determine whether a switched network may satisfy the time constraints of a real-time application. If switched architecture are interesting in the sense that they offer flexible design and may eliminate collisions in Ethernet-based net-work, they are not...

    Provided By ICST

  • White Papers // Jun 2012

    Estimation of Time-Domain Calibration Parameters to Restore MIMO-TDD Channel Reciprocity

    Spatial interweave cognitive radio opportunistically exploits spatial holes to enable transmission of secondary systems. The latter form carefully aligned spatial beams so that there is no interference to the primary system. This requires acquisition of the (spatio-temporal) Channel State (CS) between the secondary emitter and the primary receiver. CS can...

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  • White Papers // Jun 2012

    Dimensioning of Secondary Cellular System in TVWS

    The attractiveness of TV white space depends on the cost of secondary network. The cost mainly depends on the number of deployed cell sites. Traditionally, the required number of sites is estimated at the dimensioning stage of the network planning process. However, in TVWS the amount of available spectrum and...

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  • White Papers // Jun 2012

    Combination of DOA and Beamforming in Position-Based Routing for Underlay Cognitive Wireless Networks

    This paper presents a routing strategy for underlay cognitive wireless networks combining a position-based routing protocol, with position information obtained by means of Direction Of Arrival (DOA) estimation, with beamforming. Beamforming takes advantage of the estimated DOAs to maximize Signal-to-Noise Ratio at the intended receiver while minimizing interference towards potential...

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  • White Papers // Jun 2012

    Bayesian Approach to Spectrum Sensing for Cognitive Radio Applications

    In this paper, the authors address the spectrum sensing task of cognitive radio from Bayesian Detection (BD) perspective. They first show that BD essentially simplifies to classical Energy Detection (ED) under Gaussian signal assumption but the threshold setting has more degrees of freedom to optimize the sensing performance, e.g., against...

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  • White Papers // Jun 2012

    Coexistence-Aware Scheduling for LTE and WLAN During Hard In-Device Interference

    In-device interference of concurrently active radios can cause significant performance degradation in small devices such as smart phones. To avoid interference-related conflicts under challenging in-device conditions, the authors propose a generic radio scheduling architecture to the smart phone and small but important extensions to the LTE and WLAN protocols. To...

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  • White Papers // Jun 2012

    On the Permissible Transmit Power for Secondary User in TV White Spaces

    Secondary spectrum access to TV white spaces is considered as a promising solution to relieve the spectrum shortage. In Europe, SE43 working group in CEPT is leading the discussion on the technical requirements for exploiting TV white spaces through the recent ECC report 159. Its analytical approach for determining the...

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  • White Papers // Jun 2012

    Locally Best Invariant Test for Multiple Primary User Spectrum Sensing

    The authors consider multi-antenna cooperative spectrum sensing in cognitive radio networks, when there may be multiple primary users. A noise-uncertainty-free detector that is optimal in the low signal to noise ratio regime is analyzed in such a scenario. Specifically, they derive the exact moments of the test statistics involved, which...

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  • White Papers // Jun 2012

    Energy and Throughput Tradeoff in Temporal Spectrum Sharing

    It is envisaged that diverse types of short-range wireless systems coexist in shared spectrum in a near future. For low-power systems, throughput and energy efficiency are two design objectives that often conflict with each other. In this paper, the authors investigate the tradeoff between the throughput and the energy efficiency...

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  • White Papers // Jun 2012

    Aggregate Interference From WLAN in the TV White Space by Using Terrain-Based Channel Model

    In this paper, the authors model the TV white space usage by a WLAN type secondary network. They derive a model that incorporates spatially non-uniform distributed user demand and terrain-based radio channel model. They follow the approach proposed by Electronic Communications Committee (ECC) and describe the interference from the pixels...

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  • White Papers // Jun 2012

    TV White Space Channel Allocation With Simulated Annealing as Meta Algorithm

    When developing a TV White Space (TVWS) system with the available TV spectrum after digital switchover, channel allocation for TVWS devices to avoid interference becomes one of the most challenging problems. In this paper, Simulated Annealing (SA) is applied to solve the problem to minimize the total interference. However, the...

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  • White Papers // Jun 2012

    Predictive Behavior Classification for Cognitive Radio: Introduction and Preliminary Results

    Cognitive Radio systems rely heavily on artificial intelligence capabilities to perform a variety of tasks. Sharing spectrum resources more efficiently, self organization, and interference mitigation are just a few examples. For many CR applications, a primary goal is to decentralize and distribute network functions among participant nodes. As a consequence,...

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  • White Papers // Jun 2012

    Exploiting Knowledge Management for Supporting Spectrum Selection in Cognitive Radio Networks

    In order to increase Cognitive Radio operation efficiency, this paper builds up a new knowledge management functional architecture for supporting spectrum management. It integrates the fittingness factor concept proposed by the authors in a prior work and includes a set of advanced statistics capturing the influence of the radio environment....

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  • White Papers // Jun 2012

    A Software Defined Testbed for Reconfigurable Antenna Cognitive Radio

    A cognitive radio is capable of sensing local radio conditions and adapting its transmission and reception parameters to optimize performance in the evolving network environment. The use of Software Defined Radio (SDR) to make communications more flexible has greatly facilitated the design of cognitive radios, by making communications reconfigurable at...

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  • White Papers // Jun 2012

    Adaptive Model Based on Proactive Spectrum Sensing for Emergency Cognitive Ad hoc Networks

    Emergency Cognitive Ad hoc Networks (ECANs) require proactive, adaptive and resource efficient spectrum sensing. In general, work in the area of spectrum sensing for cognitive radio networks, has been focused on improving the performance and resource efficiency in static models based on reactive sensing. In this paper, an adaptive model...

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  • White Papers // Jun 2012

    Joint Channel and User Selection for Transmission and Sensing in Cognitive Radio Networks

    Cooperation among several secondary users for successful spectrum sensing defines an upper bound on the number of channels that can be sensed. Consequently, the maximum utilization is bounded by the number of sensing nodes rather than the availability of the channels. Hence, a subset of the channels should be selected...

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  • White Papers // Jun 2012

    A Model Based Approach for Estimating Aggregate Interference in Wireless Networks

    In this paper, the authors discuss the problem of estimating aggregate interference in large scale wireless networks. They argue that the usual approximations assuming uniform distribution of transmitters can lead into significant approximation errors. They then show how these approximation errors can be reduced by adopting a model based approach...

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  • White Papers // Jun 2012

    Two Days of Spectrum Use in Europe

    In this paper, the authors report on spectrum use measurements carried out synchronously over the period of 48+ hours in seven European cities. Special care has been placed on harmonizing the measurement settings and equipment so as to obtain as comparable data as possible. They describe in detail the measurement...

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  • White Papers // Jun 2012

    Location Estimation of Radio Transmitters Based on Spatial Interpolation of RSS Values

    Detection of potential transmitters' location is one of the vital aspects for efficient practical deployment of secondary spectrum access solutions. It requires accurate and up-to-date radio environmental estimation. Spatial interpolation techniques can allow partial or complete insight into the radio field, the interference and the possible geo-locations of various field...

    Provided By ICST