KTH - Royal Institute of Technology

Displaying 41-80 of 100 results

  • White Papers // Sep 2010

    Run-Time Partitioning of Hybrid Distributed Shared Memory on Multi-Core Network-on-Chips

    On multi-core Network-on-Chips (NoCs), memories are preferably distributed and supporting Distributed Shared Memory (DSM) is essential for the sake of reusing huge amount of legacy code and easy programming. However, the DSM organization imports the inherent overhead of translating virtual memory addresses into physical memory addresses, resulting in negative performance....

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2010

    CSI Acquisition Concepts for Advanced Antenna Schemes in the WINNER+ Project

    This paper summarizes four novel advanced antenna concepts explored in the framework of the WINNER+ project. The concepts are related to multiuser MIMO communication in cellular networks, focusing on the acquisition and application of Channel State Information (CSI) at the transmitter in Time-Division-Duplex (TDD) mode. The concepts include new ideas...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2010

    Feedback Design in Multiuser MIMO Systems Using Quantization Splitting and Hybrid Instantaneous/Statistical Channel Information

    In the design of next generation multiuser communication systems, multiple antenna transmission is an essential part providing spatial multiplexing gain and allowing efficient use of resources. A major limiting factor in the resource allocation is the amount of Channel State Information (CSI) available at the transmitter, particularly in multiuser systems...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2010

    Revenue Requirements for Mobile Operators With Ultra-High Mobile Broadband Data Traffic Growth

    Mobile broadband data access over cellular networks has been established as a major new service in just a few years. The mobile broadband penetration has risen from almost zero to between 10 and 15 per cent in Western European leading markets from 2007 to the end of 2009. More than...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2010

    Analysis of Roles and Position of Mobile Network Operators in Mobile Payment Infrastructure

    A number of different mobile payment solutions have been presented the last decade. The phone subscription with its security mechanisms are used for user identification and payments. This is the case for SMS based payment and ticketing systems that are getting more and more popular. However, there are other ways...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2010

    Mobile Broadband Expansion Calls for More Spectrum or Base Stations - Analysis of the Value of Spectrum and the Role of Spectrum Aggregation

    The breakthrough for mobile broadband is taking the mobile communications industry into a new phase. The number of mobile broadband users in the world exceeds 400 million, and the share of the population in Western Europe with mobile broadband is around 10 percent and over 15 percent in Austria and...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2010

    Distributed Multichannel Random Access Networks With Selfish Users

    Dynamic Spectrum Access (DSA) schemes allow the users to share spectrum resources by taking advantage of the variations in spectrum demand over time and space. Carrying out dynamic spectrum allocation centrally, however, can be a complex task. For this reason, distributed schemes in which users can access the available channels...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2010

    Experimental Verification of Indoor TV White Space Opportunity Prediction Model

    Recent work has demonstrated that the underutilized spectrum in the Digital Television Bands, commonly referred to as TV White Space (TVWS), is a prime candidate for Opportunistic Spectrum Access (OSA). However, a systematic assessment of the availability of this spectrum for secondary transmission was, until very recently, lacking. In a...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2010

    Delay-Constrained Maximum Reliability Routing Over Lossy Links

    This paper studies the problem of joint routing and transmission scheduling for reliable real-time communication over lossy networks. The authors impose a strict latency bound on the packet delivery from source to destination and develop transmission scheduling policies that maximize the probability that the packet is delivered within the specified...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Aug 2010

    Breath: An Adaptive Protocol for Industrial Control Applications Using Wireless Sensor Networks

    An energy-efficient, reliable and timely data transmission is essential for Wireless Sensor Networks (WSNs) employed in scenarios where plant information must be available for control applications. To reach a maximum efficiency, cross layer interaction is a major design paradigm to exploit the complex interaction among the layers of the protocol...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jul 2010

    Relay-Aided Multi-Cell Broadcasting With Random Network Coding

    The authors investigate a relay-aided multi-cell broadcasting system using random network codes, where the focus is on devising efficient scheduling algorithms between relay and base stations. Two scheduling algorithms are proposed based on different feedback strategies; namely, a one-step scheduling algorithm with instantaneous feedback for each redundancy packet; and a...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jul 2010

    Optimality of LDGM-LDPC Compound Codes for Lossy Compression of Binary Erasure Source

    The authors consider the Binary Erasure Source (BES) introduced by Martinian and Yedidia. Based on the technique introduced by Martinian and Wainwright, they upper bound the rate-distortion performance of the check regular Poisson LDGM ensemble and the compound LDGM-LDPC ensemble for the BES. They also show that there exist compound...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jul 2010

    Handling Shared Variable Synchronization in Multi-Core Network-on-Chips With Distributed Memory

    Parallelized shared variable applications running on multi-core Network-on-Chips (NoCs) require efficient support for synchronization, since communication is on the critical path of system performance and contended synchronization requests may cause large performance penalty. In this paper, the authors propose a dedicated hardware module for synchronization management. This module is called...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jul 2010

    LT Coded MSK Over AWGN Channels

    The authors investigate the design of Luby Transform (LT) codes with Minimum-Shift-Keying (MSK) modulation over Additive White Gaussian Noise (AWGN) channels. Both systematic and nonsystematic LT codes are considered from the perspectives of decoding threshold and bit error rate. Using systematic LT codes, coding complexity can be reduced by eliminating...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jun 2010

    Bounds on Thresholds Related to Maximum Satisfiability of Regular Random Formulas

    A literal of a Boolean variable is the variable itself or its negation. A clause is a disjunction (OR) of k literals. A formula is a conjunction (AND) of a finite set of clauses. A k-SAT formula is a formula where each clause is a disjunction of k literals. A...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jun 2010

    Financial Crises And European Regulatory Frameworks

    The current crisis in the financial system has resulted in many calls for approaches to the handling of financial service firms in crisis. Crises in the financial system are not a new phenomenon - some 93 countries have experienced crises in their financial systems since the 1970s - but even...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Apr 2010

    Supporting Efficient Synchronization in Multi-Core NoCs Using Dynamic Buffer Allocation Technique

    This paper explores a dynamic buffer allocation technique to guide distributed synchronization architecture to support efficient synchronization on multi-core Network-on-Chips (NoCs). The synchronization architecture features two physical buffers to be able to concurrently queue and handle synchronization requests issued by the local processor and remote processors via the on-chip network....

    Provided By KTH - Royal Institute of Technology

  • White Papers // Mar 2010

    An Approach to Network Security Assessment Based on Probalistic Relational Models

    To assist rational decision making regarding network security improvements, decision makers need to be able to assess weaknesses in existing or potential new systems. This paper presents a model based assessment framework for analyzing the network security provided by different architectural scenarios. The framework uses a probabilistic relational model to...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Mar 2010

    Accurate Delay Analysis of Slotted IEEE 802.15.4 for Control Applications

    To understand the fundamental performance limits and the quality of service offered by the IEEE 802.15.4 standard for control applications, the packet delay distribution plays a major role. Due to the random backoff mechanism employed by the IEEE 802.15.4 medium access protocol (MAC), it is difficult to derive such a...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Feb 2010

    Optimal Link Scheduling and Channel Assignment for Convergecast in Linear WirelessHART Networks

    There is a strong current interest in migrating substantial parts of the traditionally wired industrial infrastructure to wireless technologies to improve flexibility, scalability, and efficiency. However, concerns about network latency, reliability and security along with the lack of device interoperability have hampered the deployment rate. To address these concerns, WirelessHART,...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Feb 2010

    Remittances And Investment

    This paper studies the impact of remittances on investment. Workers' remittances to developing countries have grown to be an important source of financing, amounting to around $300 billion a year. The funds are used for both consumption and investment in the home countries of the migrants. The importance of financial...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jan 2010

    Advances in Device-to-Device Communications and Network Coding for IMT-Advanced

    In this paper, the authors introduce two innovative concepts which have not been present in cellular systems for IMT-Advanced so far: Device-To-Device (D2D) communication and network coding. Both of them are promising techniques to increase the efficiency of cellular communication systems, especially from a network point of view. They study...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Dec 2009

    Adaptive IEEE 802.15.4 Protocol for Reliable and Timely Communications

    The authors present an adaptive Medium Access Control (MAC) design for minimizing the power consumption while guaranteeing reliability and delay constraints, which is developed for the slotted IEEE 802.15.4 standard. By considering the Bianchi's MAC model, they present a generalized Markov chain model and the usage of MAC model in...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Dec 2009

    Limitations of Robust Control Over WSN: UFAD Control in Intelligent Buildings

    Intelligent buildings ventilation control is a challenging automation problem with objectives that rise several research problems of immediate actuality, such as the wireless automation and the control of complex interconnected subsystems. The system considered is composed of ventilated rooms, fans, plenums and a wireless network. The complexity arises from the...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Dec 2009

    Scalability of Relaxed Consistency Models in NoC Based Multicore Architectures

    This paper studies realization of relaxed memory consistency models in the network-on-chip based Distributed Shared Memory (DSM) multi-core systems. Within DSM systems, memory consistency is a critical issue since it affects not only the performance but also the correctness of programs. The authors investigate the scalability of the relaxed consistency...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Nov 2009

    Supporting Distributed Shared Memory on Multi-Core Network-on-Chips Using a Dual Microcoded Controller

    Supporting Distributed Shared Memory (DSM) is essential for multi-core Network-on-Chips for the sake of reusing huge amount of legacy code and easy programmability. The authors propose a microcoded controller as a hardware module in each node to connect the core, the local memory and the network. The controller is programmable...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Nov 2009

    Opportunistic Relay Selection for Wireless Network Coding

    Owing to its potential of enhancing the network performance and to the large number of applications it can be suited for, wireless network coding is attracting a lot of interest from both the academic and the industrial communities. A common assumption in most of the literature is the presence of...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Oct 2009

    A Reconfigurable Design Framework for FPGA Adaptive Computing

    Partial Reconfiguration (PR) offers the possibility to adaptively change part of the FPGA design without stopping the remaining system. In this paper, the authors present a comprehensive framework for adaptive computing, in which design key points of hardware processes, system interconnections, Operating Systems (OS), device drivers, scheduler software as well...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Oct 2009

    A Cross-Layer Protocol for Wireless Sensor Networks in Control and Automation

    Control applications over Wireless Sensor Networks (WSNs) require timely, reliable, and energy efficient communications. Cross layer interaction is an essential design paradigm to exploit the complex interaction among the layers of the protocol stack and reach a maximum efficiency. Such a design approach is challenging because reliability and latency of...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2009

    Protocol Design for Control Applications Using Wireless Sensor Networks

    Given the potential benefits offered by Wireless Sensor Networks (WSNs), they are becoming an appealing technology for process, manufacturing, and industrial control applications. In this paper, the authors propose a novel approach to WSN protocol design for control applications. The protocols are designed to minimize the energy consumption of the...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2009

    Live Migration of Virtual Machines: Sustaining Active TCP-Sessions

    Virtualization and the technology associated with it, has attracted quite a lot of attention during the past years. As of 2009, it is estimated that the market for virtualized X86 server solutions will be worth in the vicinity of $1.8 Billion. So far, the main advantages presented by virtual solution...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Aug 2009

    MAC Protocol Engine for Sensor Networks

    This paper presents a novel approach for Medium Access Control (MAC) protocol design based on protocol engine. Current way of designing MAC protocols for a specific application is based on two steps: First the application specifications (such as network topology and packet generation rate), the requirements for energy consumption, delay...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jul 2009

    Time Allocation in Wireless Network Coding

    Network coding is attracting significant research interest from the academic and industrial research communities, mainly due to its simplicity of application and the large number of applications it can be suited for. Recently, more works have been targeting wireless network coding as the broadcast properties of the wireless medium render...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jul 2009

    LQG and Medium Access Control

    The communication channel is a shared resource in networked control systems, and channel access at every instant cannot be guaranteed. In this paper, the authors propose a novel architecture for control over wireless networks with integrated Medium Access Control (MAC).They evaluate the impact of constrained channel access on the cost...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jun 2009

    Resource Allocation for QoS On-Chip Communication

    The provision of communication services with well defined performance characteristics has received significant attention in the NoC community because for many applications it is not sufficient or adequate to simply maximize average performance. It is envisioned that complex NoC based architectures will host complex, heterogeneous sets of applications. In a...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jun 2009

    A Flow Regulator for On-Chip Communication

    IPs for a SoC are typically developed concurrently using a standard interface, for example, AXI or OCP. Despite the standard interfaces, integrating IPs to a SoC infrastructure presents challenges because traffic flows from IPs are diverse and typically have stringent performance constraints; the impact of interferences among traffic flows is...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jun 2009

    Scheduling Packets for Event-Triggered Control

    There is a tight interaction between the control architecture and the communication protocols in networked control systems. Periodic time-triggered control loops are natural to use together with a TDMA scheduled communication medium, while a periodic event-triggered control loops are suitable for contention-based medium access. Only recently has a thorough study...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jun 2009

    Trigger Algorithm Development on FPGA-Based Compute Nodes

    Based on the ATCA computation architecture and Compute Nodes (CN), investigation and implementation work has been being executed for HADES and PANDA trigger algorithms. The authors present the designs for HADES track reconstruction processing, Cherenkov ring recognition, Time-Of-Flight processing, electromagnetic shower recognition, and the PANDA straw tube tracking algorithm. They...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jun 2009

    Run-Time Partial Reconfiguration Speed Investigation and Architectural Design Space Exploration

    Run-time Partial Reconfiguration (PR) speed is significant in applications especially when fast IP core switching is required. In this paper, the authors propose to use Direct Memory Access (DMA), Master (MST) burst, and a dedicated Block RAM (BRAM) cache respectively to reduce the reconfiguration time. Based on the Xilinx PR...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Apr 2009

    Modelling Business Transactions from the Value and Collaboration Perspective

    Business collaborations between actors encompass different business objectives, such as making product awareness, buying or selling specific products or goods, providing post-sale services, and so forth. Thereby, a clear identification of required business transactions is vital for modeling complex business collaboration, as well as for their further implementation with IT...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2008

    Deadline-Constrained Transmission Scheduling and Data Evacuation in WirelessHART Networks

    Real-time data delivery is a critical issue in wirelessHART networks. This paper develops a novel mathematical programming framework for joint routing and link scheduling of deadline-constrained traffic in wirelessHART networks. The general framework explores dynamic network flows in a time-expanded graph model and can provide flexible solutions for a variety...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jan 2009

    Efficient Link Scheduling and Channel Hopping for Convergecast in Wireless HART Networks

    There is a strong current interest in migrating substantial parts of the traditionally wired industrial infrastructure to wireless technologies to improve flexibility, scalability, and efficiency. However, concerns about network latency, reliability and security along with the lack of device interoperability have hampered the deployment rate. To address these concerns, WirelessHART,...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Feb 2011

    A Mobile World of Security - The Model

    The authors propose a novel approach to establish cryptographic keys among mobile users and a networking infrastructure. Their approach comes at a low cost and can either be used as an alternative to existing solutions or can be employed in a complementary way. Their basic observation is that users are...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Apr 2011

    How Far from Kronecker can a MIMO Channel be? Does it Matter?

    A common assumption in the design and analysis of many MIMO transmission schemes is the so-called Kronecker model. This model is often a crucial step to obtain mathematically tractable solutions, but has also been criticized for being unrealistic. In this paper, the authors present a numerical approach to determine a...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jul 2009

    Time Allocation in Wireless Network Coding

    Network coding is attracting significant research interest from the academic and industrial research communities, mainly due to its simplicity of application and the large number of applications it can be suited for. Recently, more works have been targeting wireless network coding as the broadcast properties of the wireless medium render...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Dec 2010

    Advances in Wireless Network Coding for IMT-Advanced & Beyond

    In a classical network, data streams originating from a source and intended to a desired destination are routed through intermediate nodes before reaching their final destination. By contrast, Network Coding (NC) manipulates at an intermediate node those data streams by combining the data from the streams before forwarding it to...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Nov 2009

    Opportunistic Relay Selection for Wireless Network Coding

    Owing to its potential of enhancing the network performance and to the large number of applications it can be suited for, wireless network coding is attracting a lot of interest from both the academic and the industrial communities. A common assumption in most of the literature is the presence of...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2010

    CSI Acquisition Concepts for Advanced Antenna Schemes in the WINNER+ Project

    This paper summarizes four novel advanced antenna concepts explored in the framework of the WINNER+ project. The concepts are related to multiuser MIMO communication in cellular networks, focusing on the acquisition and application of Channel State Information (CSI) at the transmitter in Time-Division-Duplex (TDD) mode. The concepts include new ideas...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2010

    Delay-Constrained Maximum Reliability Routing Over Lossy Links

    This paper studies the problem of joint routing and transmission scheduling for reliable real-time communication over lossy networks. The authors impose a strict latency bound on the packet delivery from source to destination and develop transmission scheduling policies that maximize the probability that the packet is delivered within the specified...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2010

    Feedback Design in Multiuser MIMO Systems Using Quantization Splitting and Hybrid Instantaneous/Statistical Channel Information

    In the design of next generation multiuser communication systems, multiple antenna transmission is an essential part providing spatial multiplexing gain and allowing efficient use of resources. A major limiting factor in the resource allocation is the amount of Channel State Information (CSI) available at the transmitter, particularly in multiuser systems...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Nov 2010

    On the Use of Compressive Sampling for Wide-Band Spectrum Sensing

    In a scenario where a cognitive radio unit wishes to transmit, it needs to know over which frequency bands it can operate. It can obtain this knowledge by estimating the power spectral density from a Nyquist-rate sampled signal. For wide-band signals sampling at the Nyquist rate is a major challenge...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Feb 2009

    Automated Multidimensional Characterization of Power Amplifier for Design and Production

    Designing, optimizing and producing modern Power Amplifiers (PA) requires new and fast RF (Radio Frequency) measurement techniques capable of characterizing its real behavior. PAs are a truly multidimensional device where many desired performance parameters are contradictory to each other. This is especially true for the generation of modern communication PAs...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Mar 2009

    Experiences on Mobile-ATM Deployment in a Developing Country

    Mobile-Commerce is the latest concept of enabling the financial transactions on mobile phones and hand-held devices. With the rapid development of the society, the M-Commerce applications play a vital role. Mobile-ATM is one such application, enabling the banking services on mobile phones. Even though users have a poor computer literacy,...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Aug 2011

    P2P Social Networks With Broadcast Encryption Protected Privacy

    Existing centralized, provider-dependent networks do not provide users with mechanisms to fully protect their data. The provider has complete control of the service, and users have to rely on security mechanisms provided by the service. There is no guarantee that the trusted provider will enforce the privacy preferences of the...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Aug 2011

    Encryption for Peer-to-Peer Social Networks

    To address privacy concerns over online social networking services, several distributed alternatives have been proposed. These Peer-To-Peer (P2P) online social networks do not rely on centralized storage of user data. Instead, data can be stored not only on a computer of a profile owner but almost anywhere (friends' computers, random...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jan 2011

    Sphere Decoding Complexity Exponent for Full Rate Codes Over the Quasi-Static MIMO Channel

    In the setting of quasi-static Multiple-Input Multiple-Output (MIMO) channels, the authors consider the high Signal-to-Noise Ratio (SNR) asymptotic complexity required by the Sphere Decoding (SD) algorithm for decoding a large class of full rate linear space-time codes. With SD complexity being a function of the code and having random fluctuations...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jan 2012

    Approximation for a Sum of On-Off Log-Normal Processes With Wireless Applications

    In this paper, a log-normal approximation is proposed for the sum of log-normal processes weighted by binary processes. The analytical approach moves from the method early proposed by Wilkinson for approximating first order statistics of a sum of log-normal components, and extends to incorporate second order statistics and the presence...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Mar 2012

    On Rate Allocation for Multiple Plants in a Networked Control System

    The problem of allocating communication resources to multiple plants in a networked control system is investigated. In the presence of a shared communication medium, a total transmission rate constraint is imposed. For the purpose of optimizing the rate allocation to the plants over a finite horizon, two objective functions are...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jan 2011

    Power and Rate Control Outage Based in CDMA Wireless Networks Under MAI and Heterogeneous Traffic Sources

    The authors characterize the maximum throughput achievable for the up-link of a power-controlled WCDMA wireless system with variable spreading factor. Their system model includes multi access interference caused by users with heterogeneous data sources, and quality of service expressed in terms of outage probability. Inner loop and outer loop power...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jan 2012

    State-of-The Art and Future In-Car Navigation Systems - A Survey

    A survey of the information sources and information fusion technologies used in the current in-car navigation systems is presented. The pros and cons of the four commonly used information sources - GNSS/RF-based positioning, vehicle motion sensors, vehicle models and map information - are described. Common filters to combine the information...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jul 2010

    Optimality of LDGM-LDPC Compound Codes for Lossy Compression of Binary Erasure Source

    The authors consider the Binary Erasure Source (BES) introduced by Martinian and Yedidia. Based on the technique introduced by Martinian and Wainwright, they upper bound the rate-distortion performance of the check regular Poisson LDGM ensemble and the compound LDGM-LDPC ensemble for the BES. They also show that there exist compound...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jul 2010

    LT Coded MSK Over AWGN Channels

    The authors investigate the design of Luby Transform (LT) codes with Minimum-Shift-Keying (MSK) modulation over Additive White Gaussian Noise (AWGN) channels. Both systematic and nonsystematic LT codes are considered from the perspectives of decoding threshold and bit error rate. Using systematic LT codes, coding complexity can be reduced by eliminating...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jul 2010

    Relay-Aided Multi-Cell Broadcasting With Random Network Coding

    The authors investigate a relay-aided multi-cell broadcasting system using random network codes, where the focus is on devising efficient scheduling algorithms between relay and base stations. Two scheduling algorithms are proposed based on different feedback strategies; namely, a one-step scheduling algorithm with instantaneous feedback for each redundancy packet; and a...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jun 2010

    Bounds on Thresholds Related to Maximum Satisfiability of Regular Random Formulas

    A literal of a Boolean variable is the variable itself or its negation. A clause is a disjunction (OR) of k literals. A formula is a conjunction (AND) of a finite set of clauses. A k-SAT formula is a formula where each clause is a disjunction of k literals. A...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jun 2011

    Myopic Multi-Hop Transmission Strategies in Layered Wireless Networks

    A layered wireless network is considered, where information is transmitted in a multi-hop MIMO-like fashion from the source node layer through several intermediate layers of nodes before reaching the sink node layer. Analog network coding is investigated as the network transmission strategy, exploiting the inherent superposition features of the wireless...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jul 2011

    Error Floor Analysis of LT Codes Over the Additive White Gaussian Noise Channel

    The authors investigate the error floor performance of Luby Transform (LT) codes over the additive white Gaussian noise channel. They first derive a lower bound on the bit error rate for an LT code, which they subsequently use to show that the corresponding error floor is predominantly caused by low-degree...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Feb 2011

    Relay-Aided Broadcasting With Instantaneously Decodable Binary Network Codes

    The authors consider a base-station broadcasting a set of order-insensitive packets to a user population over packet-erasure channels. To improve efficiency they propose a relay-aided transmission scheme using instantaneously-decodable binary network coding. Their proposed scheme ensures that a coded packet can be immediately decoded at the user side without delay....

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jul 2011

    Efficient Scheduling for Relay-Aided Broadcasting With Random Network Codes

    The authors investigate efficient scheduling algorithms for a relay-aided broadcasting system using random network codes, where their objective is to maximize the transmission efficiency. The broadcast from a Base-Station (BS) is divided into an information phase and a redundancy phase, where the half-duplex relay assists in the redundancy phase. Time-division...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2011

    A Constrained Optimization Approach to Nonlinear Interference Cancellation

    Non-linear interference cancellation has been successful as a low-complexity iterative detection strategy for multiple-input, multiple-output channels. However, such strategies are generally difficult to analyze. Here, the authors develop a connection to constrained optimization through the use of penalty functions. The resulting framework provides a means of analysis, and includes known...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Feb 2012

    Real-Time Scheduling in LTE for Smart Grids

    The latest wireless network, 3GPP Long Term Evolution (LTE), is considered to be a promising solution for smart grids because it provides both low latency and large bandwidth. However, LTE was not originally intended for smart grids applications, where data generated by the grid have specific delay requirements that are...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Aug 2012

    A Conservation-Law-Based Modular Fluid-Flow Model for Network Congestion Modeling

    A modular fluid-flow model for network congestion analysis and control is proposed. The model is derived from an information conservation law stating that the information is either in transit, lost or received. Mathematical models of network elements such as queues, users, and transmission channels, and network description variables, including sending/...

    Provided By KTH - Royal Institute of Technology

  • White Papers // May 2011

    Compress-and-Forward Relaying Based on Symbol-Wise Joint Source-Channel Coding

    The authors propose a new compress-and-forward implementation for the relay channel based on joint source-channel coding techniques. The relay performs scalar quantization of its observation in combination with a redundant index mapping. The system utilizes the correlation between the quantized signal and the direct-link observation of the transmitted symbols as...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2010

    Distributed Multichannel Random Access Networks With Selfish Users

    Dynamic Spectrum Access (DSA) schemes allow the users to share spectrum resources by taking advantage of the variations in spectrum demand over time and space. Carrying out dynamic spectrum allocation centrally, however, can be a complex task. For this reason, distributed schemes in which users can access the available channels...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Sep 2010

    Experimental Verification of Indoor TV White Space Opportunity Prediction Model

    Recent work has demonstrated that the underutilized spectrum in the Digital Television Bands, commonly referred to as TV White Space (TVWS), is a prime candidate for Opportunistic Spectrum Access (OSA). However, a systematic assessment of the availability of this spectrum for secondary transmission was, until very recently, lacking. In a...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jan 2009

    Priority Based Forced Requeue to Reduce Worst-Case Latencies for Bursty Traffic

    In this paper the authors introduce Priority Based Forced Requeue to decrease worst-case latencies in NoCs offering best effort services. Forced Requeue is to prematurely lift out low priority packets from the network and requeue them outside using priority queues. The first benefit of this approach, applicable to any NoC...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jan 2009

    Flow Regulation for On-Chip Communication

    IPs for a SoC are typically developed concurrently using a standard interface, for example, AXI or OCP. Despite the standard interfaces, integrating IPs to a SoC infrastructure presents challenges because traffic flows from IPs are diverse and typically they have stringent performance constraints; the impact of interferences among traffic flows...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jun 2009

    Run-Time Partial Reconfiguration Speed Investigation and Architectural Design Space Exploration

    Run-time Partial Reconfiguration (PR) speed is significant in applications especially when fast IP core switching is required. In this paper, the authors propose to use Direct Memory Access (DMA), Master (MST) burst, and a dedicated Block RAM (BRAM) cache respectively to reduce the reconfiguration time. Based on the Xilinx PR...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jun 2009

    Resource Allocation for QoS On-Chip Communication

    The provision of communication services with well defined performance characteristics has received significant attention in the NoC community because for many applications it is not sufficient or adequate to simply maximize average performance. It is envisioned that complex NoC based architectures will host complex, heterogeneous sets of applications. In a...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Feb 2009

    High-Level Estimation and Trade-Off Analysis for Adaptive Real-Time Systems

    The authors propose a novel design estimation method for adaptive streaming applications to be implemented on a partially reconfigurable FPGA. Based on experimental results they enable accurate design cost estimates at an early design stage. Given the size and computation time of a set of configurations, which can be derived...

    Provided By KTH - Royal Institute of Technology

  • White Papers // Jun 2009

    Trigger Algorithm Development on FPGA-Based Compute Nodes

    Based on the ATCA computation architecture and Compute Nodes (CN), investigation and implementation work has been being executed for HADES and PANDA trigger algorithms. The authors present the designs for HADES track reconstruction processing, Cherenkov ring recognition, Time-Of-Flight processing, electromagnetic shower recognition, and the PANDA straw tube tracking algorithm. They...

    Provided By KTH - Royal Institute of Technology