University of South Florida

Displaying 1-40 of 121 results

  • White Papers // Apr 2014

    SPARQL Query Verbalization for Explaining Semantic Search Engine Queries

    SPARQL is the W3C recommendation for querying and accessing RDF data. While it has found broad acceptance among semantic application developers, its usage among those who possess limited to no expertise in semantic technologies remains understandably limited. In this paper, the authors introduce Spartiqulation, a system that translates SPARQL queries...

    Provided By University of South Florida

  • White Papers // Jan 2014

    Implementation of an IEEE 802.11a Compliant Low-Power Baseband Processor

    Fourth Generation (4G) wireless and mobile systems are today very attractive for research and development. New types of services will be universally available to consumers and for industrial applications with the use of 4G devices. Broadband wireless networks will enable packet based high-speed data transfer suitable for video transmission and...

    Provided By University of South Florida

  • White Papers // Jan 2014

    A Dual-Mode Synchronous/Asynchronous CORDIC Processor

    Fourth Generation (4G) wireless and mobile systems are currently the focus of research and development. They will allow new types of services to be universally available to consumers and for industrial applications. For application in a software defined radio a CORDIC processor has been developed that can operate both in...

    Provided By University of South Florida

  • White Papers // Jan 2014

    Reducing the Energy Consumption in Fault-tolerant Distributed Embedded Systems with Time-Constraint

    In this paper, the authors address the problem of reducing the energy consumption in distributed embedded systems associated with time-constraints and equipped with fault-tolerant techniques. A greedy heuristic is presented to reduce the energy during task mapping and fault tolerance policy assignment. Fault tolerance is achieved through task re-execution and...

    Provided By University of South Florida

  • White Papers // Jan 2014

    Cost Model-Driven Test Resource Partitioning for SoCs

    The main factors contributing to the cost of System-on-Chip (SoC) manufacturing test are the required number of tester pins, the test application time, the tester memory requirements and the area overhead required by the test resources. These factors contribute with different weights, depending on the cost model of each SOC....

    Provided By University of South Florida

  • White Papers // Dec 2013

    An Improved Instruction-Level Power Model for ARM11 Microprocessor

    Low power consumption is becoming more and more important, because a lot of embedded systems use batteries as energy sources. To make a low power processor, a number of hardware techniques have been developed, such as clock gating and power gating. Software also affects the power consumption, but there is...

    Provided By University of South Florida

  • White Papers // Aug 2013

    Applying of Quality of Experience to System Optimisation

    State-of-the-art mobile devices, such as Smartphone's and tablets, are highly versatile and must deliver high performance across a multitude of applications. The perceived performance and resulting user experience can make or break a design. It is therefore vital that device design and optimization take into account the expectations and perceptions...

    Provided By University of South Florida

  • White Papers // Jun 2013

    Untainted Puncturing for Irregular Low-Density Parity-Check Codes

    Puncturing is a well-known coding technique widely used for constructing rate-compatible codes. In this paper, the authors consider the problem of puncturing low-density parity-check codes and propose a new algorithm for intentional puncturing. The algorithm is based on the puncturing of untainted symbols, i.e. nodes with no punctured symbols within...

    Provided By University of South Florida

  • White Papers // Jun 2013

    On the Viability of Using Liability to Incentivise Internet Security

    Internet use is characterized by externalities, which means that it can be sufficiently pro table for criminal enterprises to flourish. One possible mechanism which could be considered to improve incentives is liability. The authors conduct a review of the literature relating to liability theory, liability online, and security economics in...

    Provided By University of South Florida

  • White Papers // Mar 2013

    Real Time Controller Implementation for an Atomic Force Microscope Using a Digital Signal Processor

    The objective of this contribution is to report a low cost implementation of a control system for an Atomic Force Microscope (AFM). AFMs rely on a feedback controller as an integral part of their operation. Currently the controllers shipped with most commercial AFMs are implemented in a closed source manner...

    Provided By University of South Florida

  • White Papers // Mar 2013

    Maximizing Energy-Efficiency in Multi-Relay OFDMA Cellular Networks

    This contribution presents a method of obtaining the optimal power and subcarrier allocations that maximize the Energy-Efficiency (EE) of a multi-user, multi-relay, Orthogonal Frequency Division Multiple Access (OFDMA) cellular network. Initially, the Objective Function (OF) is formulated as the ratio of the Spectral-Efficiency (SE) over the power consumption of the...

    Provided By University of South Florida

  • White Papers // Mar 2013

    Cross-Layer Aided Energy-Efficient Opportunistic Routing in Ad Hoc Networks

    Most of the nodes in ad hoc networks rely on batteries, which requires energy saving. Hence, numerous energy-efficient routing algorithms have been proposed for solving this problem. In this paper, the authors exploit the benefits of cross-layer information exchange, such as the knowledge of the Frame Error Rate (FER) in...

    Provided By University of South Florida

  • White Papers // Feb 2013

    Generalized Adaptive Network Coding Aided Successive Relaying for Noncoherent Cooperation

    A Generalized Adaptive Network Coding (GANC) scheme is conceived for a multi-user, multi-relay scenario, where the multiple users transmit independent information streams to a common destination with the aid of multiple relays. The proposed GANC scheme is developed from Adaptive Network Coded Cooperation (ANCC), which aims for a high flexibility...

    Provided By University of South Florida

  • White Papers // Feb 2013

    MC-CDMA Aided Multi-User Space-Time Shift Keying in Wideband Channels

    In this paper, the authors propose Multi-Carrier Code Division Multiple Access (MC-CDMA)-aided Space-Time Shift Keying (STSK) for mitigating the performance erosion of the classic STSK scheme in dispersive channels, while supporting multiple users. The codewords generated by the STSK scheme are appropriately spread in Frequency-Domain (FD) and transmitted over a...

    Provided By University of South Florida

  • White Papers // Jan 2013

    Multilevel Generalized Low-Density Parity-Check Codes

    Multi-Level Coding (MLC) was proposed by Imai and Hirawaki as a bandwidth efficient coded modulation scheme designed for protecting each bit of a non-binary symbol with the aid of binary codes, while maintaining different target Bit Error Rates (BERs). Parallel Independent Decoding (PID) is employed as an efficient decoding strategy...

    Provided By University of South Florida

  • White Papers // Jan 2013

    Modelling Interactive Real-Time Applications on Service Oriented Infrastructures

    The European Commission supported IRMOS project is developing tools and techniques that allow real-time applications to be planned and executed on distributed Service Oriented Infrastructures (SOI) operated by third-party service providers. The exemplar applications within the project are all multimedia based and include support for interactive and collaborative film post-production,...

    Provided By University of South Florida

  • White Papers // Dec 2012

    Near-Capacity Joint Channel Estimation and Three-Stage Turbo Detection for MIMO Systems

    The authors propose a novel joint channel estimation and three-stage iterative detection/decoding scheme for near-capacity MIMO systems. In their scheme, as usual, the detected soft information is first exchanged a number of times within the inner turbo loop between the Unity-Rate-Code (URC) decoder and the MIMO soft-demapper, and the information...

    Provided By University of South Florida

  • White Papers // Nov 2012

    Iterative Detection and Decoding Using Approximate Bayesian Theorem Based PDA Method Over MIMO Nakagami-M Fading Channels

    In this paper, the design of Iterative Detection and Decoding (IDD) schemes relying on a low-complexity Probabilistic Data Association (PDA) aided method is conceived for turbo-coded Multiple-Input Multiple-Output (MIMO) systems communicating over Nakagami-m fading channels. The known PDA based MIMO detectors typically operate purely in the probability-domain. The authors show...

    Provided By University of South Florida

  • White Papers // Nov 2012

    Reduced-Complexity Soft STBC Detection

    Inspired by the scientific breakthrough of Turbo Codes (TCs) proposed, a near-capacity performance has been pursued by numerous researchers in diverse system contexts. However, as the researchers have inched closer and closer to the channel capacity, the complexity of the resultant communication systems was increased. The soft-decision aided MIMO detection...

    Provided By University of South Florida

  • White Papers // Oct 2012

    User Relay Assisted Traffic Shifting in LTE-Advanced Systems

    In order to deal with uneven load distribution, mobility load balancing adjusts the handover region to shift edge users from a hot-spot cell to the less-loaded neighbouring cells. However, shifted users suffer the reduced signal power from neighbouring cells, which may result in link quality degradation. This paper employs a...

    Provided By University of South Florida

  • White Papers // Sep 2012

    DS-CDMA With M-Ary Orthogonal Modulation for Wireless Sensor Networks Simultaneously Monitoring Multiple Events

    In this paper, the authors propose a novel WSN framework for one fusion center to monitor simultaneously multiple Source Events (SEs), each of which has multiple states. In the proposed WSN, every SE is observed by a range of local sensors, which convey their observations to the fusion center in...

    Provided By University of South Florida

  • White Papers // Sep 2012

    Comparison of Remote Analysis with Statistical Disclosure Control for Protecting the Confidentiality of Business Data

    In this paper the authors concerned with the challenge of allowing statistical analysis of confidential business data while maintaining confidentiality. The most widely-used approach to date is statistical disclosure control, which involves modifying or confidentialising data before releasing it to users. Newer proposed approaches include the release of multiply imputed...

    Provided By University of South Florida

  • White Papers // Aug 2012

    A Hybrid Artificial Immune System and Self Organising Map for Network Intrusion Detection

    Network intrusion detection is the problem of detecting unauthorized use of, or access to, computer systems over a network. Two broad approaches exist to tackle this problem: anomaly detection and misuse detection. An anomaly detection system is trained only on examples of normal connections, and thus has the potential to...

    Provided By University of South Florida

  • White Papers // Aug 2012

    Beyond the Hype: Cloud Computing in Analytics

    Machine learning (ML) techniques are becoming commonplace in business and research alike. With the automatization of data collection efforts, evermore data is being captured, rendering the task of extracting insightful patterns increasingly challenging. In addition to this "data avalanche" becoming ever more overwhelming, the usage of more computationally intensive algorithms...

    Provided By University of South Florida

  • White Papers // Jul 2012

    The Business Perspective of Cloud Computing for Small and Medium Enterprises

    Cloud computing has been described as a technological change brought about by the convergence of a number of new and existing technologies. It enables all businesses to get the best of technology at extremely economical costs. Both perspectives of the Cloud are important to be reviewed, of the provider's side...

    Provided By University of South Florida

  • White Papers // May 2012

    MQBM: An Autonomic QoS Multicast Routing Protocol for Mobile Ad Hoc Networks

    Mobile Ad hoc NETwork (MANET) is a wireless network that consists of a large number of mobile and heterogeneous nodes interconnected by wireless links which move in an arbitrary direction with random velocity. It is characterized by the absence of any pre-existing infrastructure. This makes the transmission more difficult especially,...

    Provided By University of South Florida

  • White Papers // May 2012

    First-Hop-Quality-Aware Dynamic Resource Allocation for Amplify-and-Forward Opportunistic Relaying Assisted SC-FDMA

    In this paper, the authors exploit the benefits of the diversity gains arising from a cluster of Opportunistic Relays (OR) and from the independently fading subcarriers of multiple users. Their goal is to improve the energy-efficiency of the OR assisted Single-Carrier Frequency-Division Multiple-Access (SC-FDMA) uplink using Amplify-and-Forward (AF), where the...

    Provided By University of South Florida

  • White Papers // May 2012

    Selective Relaying in Multi-Relay Networks With Feedback Delays and Adaptive Modulation

    This paper evaluates the performance of adaptive modulation in multi-relay networks with selective relaying, under Nakagami-m fading. In the system model, the source decides independently whether to forward the source message to the destination via the best (partial relay selection) relay path or direct path by comparing the end-to-end instantaneous...

    Provided By University of South Florida

  • White Papers // May 2012

    Relay Selection Schemes Relying on Adaptive Modulation and Imperfect Channel Knowledge for Cooperative Networks

    Cooperative MAC protocols have been shown to increase the attainable network throughput and to reduce the outage probability when perfect Channel State Information (CSI) is available either at the source station or at candidate relays. This paper investigates the realistically achievable network performance of relay selection schemes under imperfect CSI...

    Provided By University of South Florida

  • White Papers // May 2012

    Efficient Frequency Domain Packet Scheduler for Point-to-Multipoint Transmissions in LTE Networks

    Long Term Evolution (LTE) is the emerging 4G wireless technology developed to provide high quality services in mobile environments. It is foreseen that multimedia services and mobile TV will assume an important role for the LTE proliferation in mobile market. However, several issues are still open and meaningful improvements have...

    Provided By University of South Florida

  • White Papers // May 2012

    Efficient MIMO Antenna Evaluation Based on MIMO Spatial Channel Simulations

    This paper studies the proposal of using Spatial Channel Model (SCM) for the purpose of MIMO antenna parameter evaluation. The reason of choosing SCM is firstly explained. Then field measurements are conducted for comparison with simulations. The measurements have given preliminary proof to the applicability of the simulation method. To...

    Provided By University of South Florida

  • White Papers // May 2012

    A Novel Ergodic Capacity Analysis of Diversity Combining and Multihop Transmission Systems Over Generalized Composite Fading Channels

    Ergodic capacity is an important performance measure associated with reliable communication at the highest rate at which information can be sent over the channel with a negligible probability of error. In the shadow of this definition, diversity receivers (such as selection combining, equal-gain combining and maximal-ratio combining) and transmission techniques...

    Provided By University of South Florida

  • White Papers // May 2012

    Alternative Concepts of Antenna Deployment and Cell Layout in Mobile Communications

    Cellular communication systems have traditionally been designed according to the paradigm that base stations serve independent sectors for which inter-sector interference should be minimized. Further, multiple base stations serving multiple sectors are traditionally grouped into a minimum number of sites, in order to reuse infrastructure for cooling, battery backup etc....

    Provided By University of South Florida

  • White Papers // May 2012

    Truthful Auction for Cooperative Communications With Revenue Maximization

    Auction theory has been applied to cooperative communications to either efficiently allocate resources or incentivize wireless devices to participate in cooperative communications. However, a common shortcoming of the existing studies is that the revenue generation is neglected. Revenue generation is the ultimate goal of commercial networks, e.g., WiMAX networks. In...

    Provided By University of South Florida

  • White Papers // May 2012

    Characterizing Random CSMA Wireless Networks: A Stochastic Geometry Approach

    The authors characterize the random CSMA wireless networks by statistically quantifying the intensity of simultaneously active nodes and the aggregate interference experienced by a generic node in the network. First, starting from a Poisson point process to model the spatial distribution of the network nodes, they propose a Modified Hard...

    Provided By University of South Florida

  • White Papers // May 2012

    Modeling Random CSMA Wireless Networks in General Fading Environments

    Carrier-Sense Multiple Access (CSMA) protocols coordinate the spectrum access to maximize the spatial frequency reuse and minimize the mutual interference in distributed wireless networks. Since the CSMA protocol correlates the positions of the simultaneously active transmitters, the analytically tractable Poisson Point Process (PPP) cannot be used to model the spatial...

    Provided By University of South Florida

  • White Papers // May 2012

    Reduced Feedback Links for Power Minimization in Distributed Multicell OFDMA Networks

    In the next generation of multicell networks, adaptive resource allocation techniques will play an important role to improve both quality of service and spectral efficiency. In order to employ distributed power allocation for multicell Orthogonal Frequency-Division Multiple Access (OFDMA) networks, the Channel State Information (CSI) belonging to all users is...

    Provided By University of South Florida

  • White Papers // May 2012

    Iterative Two-Dimensional Error Concealment for Low-Complexity Wireless Video Uplink Transmitters

    Since joint source-channel decoding is capable of exploiting the residual redundancy in the encoded source signals for improving the attainable error resilience, it has attracted substantial attention. Motivated by the principle of exploiting the source redundancy at the receiver, in this treatise the authors paper the application of iterative Error...

    Provided By University of South Florida

  • White Papers // Mar 2012

    Channel Quantization for Physical Layer Network-Coded Two-Way Relaying

    The design of modulation schemes for the physical layer network-coded two way relaying scenario is considered with the protocol which employs two phases: Multiple access (MA) Phase and Broadcast (BC) phase. It was observed by Koike-Akino et al. that adaptively changing the network coding map used at the relay according...

    Provided By University of South Florida

  • White Papers // Mar 2012

    On Spatial Load Balancing In Wide-Area Wireless Networks

    Load Balancing is typically used in cellular wireless networks in the frequency domain to balance paging, access, and traffic load across the available bandwidth. In this paper, the authors extend the concept of Load Balancing to the Spatial domain. They develop two approaches - Network Load Balancing and Single-Carrier MultiLink...

    Provided By University of South Florida

  • White Papers // Nov 2012

    Iterative Detection and Decoding Using Approximate Bayesian Theorem Based PDA Method Over MIMO Nakagami-M Fading Channels

    In this paper, the design of Iterative Detection and Decoding (IDD) schemes relying on a low-complexity Probabilistic Data Association (PDA) aided method is conceived for turbo-coded Multiple-Input Multiple-Output (MIMO) systems communicating over Nakagami-m fading channels. The known PDA based MIMO detectors typically operate purely in the probability-domain. The authors show...

    Provided By University of South Florida

  • White Papers // Nov 2012

    Reduced-Complexity Soft STBC Detection

    Inspired by the scientific breakthrough of Turbo Codes (TCs) proposed, a near-capacity performance has been pursued by numerous researchers in diverse system contexts. However, as the researchers have inched closer and closer to the channel capacity, the complexity of the resultant communication systems was increased. The soft-decision aided MIMO detection...

    Provided By University of South Florida

  • White Papers // Mar 2013

    Cross-Layer Aided Energy-Efficient Opportunistic Routing in Ad Hoc Networks

    Most of the nodes in ad hoc networks rely on batteries, which requires energy saving. Hence, numerous energy-efficient routing algorithms have been proposed for solving this problem. In this paper, the authors exploit the benefits of cross-layer information exchange, such as the knowledge of the Frame Error Rate (FER) in...

    Provided By University of South Florida

  • White Papers // Sep 2012

    DS-CDMA With M-Ary Orthogonal Modulation for Wireless Sensor Networks Simultaneously Monitoring Multiple Events

    In this paper, the authors propose a novel WSN framework for one fusion center to monitor simultaneously multiple Source Events (SEs), each of which has multiple states. In the proposed WSN, every SE is observed by a range of local sensors, which convey their observations to the fusion center in...

    Provided By University of South Florida

  • White Papers // Oct 2009

    A Multicast-Based Bootstrap Mechanism for Self-Organizing P2P Networks

    The Peer-To-Peer (P2P) network paradigm has been introduced in order to overcome some shortcomings of the client-server architecture by providing such features as decentralization, self-organization, scalability, and fault-tolerance. Bootstrapping is the initial process through which new nodes can join an existing P2P overlay network. Typically, a joining peer must first...

    Provided By University of South Florida

  • White Papers // Oct 2009

    A Study of Adaptive Equalizer for APSK in the Advanced Satellite Broadcasting System

    By making use of LDPC codes and a smaller roll-off factor, the advanced satellite broadcasting system proposed by the authors has a 30% higher transmission channel capacity in comparison with the current ISDB-S system. In addition, the transmission channel capacity can be more increased by using Multi-level Amplitude Phase Shift...

    Provided By University of South Florida

  • White Papers // Oct 2009

    Minimum Backup Configuration-Creation Method for IP Fast Reroute

    IP fast reroute techniques have been proposed for achieving fast failure recovery in just a few milliseconds. The basic idea of IP fast reroute is to reduce recovery time after failure by precomputing backup routes. A Multiple Routing Configurations (MRC) algorithm has been proposed for obtaining IP fast reroute. MRC...

    Provided By University of South Florida

  • White Papers // Oct 2009

    Inter-Packet Channel Estimation in OFDM Systems

    In this paper, channel estimation in the context of OFDM systems is investigated. In particular, a technique to improve the channel estimation in the current packet, by averaging out the channel estimates performed during previous packets, is proposed. However, when frame synchronization offset and/or sampling phase offset is present, the...

    Provided By University of South Florida

  • White Papers // Oct 2009

    Design Method of Robust Networks Against Performance Deterioration During Failures

    When a link or node failure occurs in a network, flows are detoured and therefore the hop counts of the flows increase. This increase could drastically deteriorate the quality of a network. The flow hop length stability as well as network connectivity is important for network reliability. The authors investigate...

    Provided By University of South Florida

  • White Papers // Oct 2009

    On-Line Hybrid Cramer-Rao Bound for Oversampled Dynamical Phase and Frequency Offset Estimation

    In this paper, the authors deal with the on-line estimation of a dynamical carrier phase and a frequency offset in a digital receiver. They consider a Brownian phase evolution with a linear drift in a data aided scenario. The proposed paper is relative to the use of an oversampled signal...

    Provided By University of South Florida

  • White Papers // Oct 2009

    Distortion Prediction for Video Quality Optimization Over Packet Switched Networks

    Scheduling techniques are often deployed at the network edge to maximize the quality of the video communication while satisfying a given constraint on the maximum high priority usable bandwidth. For the case of video communications, the importance of each packet, in terms of the distortion that would be caused by...

    Provided By University of South Florida

  • White Papers // Oct 2009

    Site-Specific RSS Signature Modeling for WiFi Localization

    A number of techniques for indoor and outdoor WiFi localization using Received Signal Strength (RSS) signatures have been published. Little work has been performed to characterize the RSS signatures used by these WiFi localization techniques or to assess the accuracy of current channel models to represent the signatures. Without accurate...

    Provided By University of South Florida

  • White Papers // Oct 2009

    Bridging the Gap Between Mathematical Traffic Models and Operational Parameters

    Over the past decade and more, several accurate but complex traffic models have been developed by just as many researchers. Among the most accurate models are those based on mathematical principles that are able to model the multifractal nature of network traffic. Unfortunately these models are hardly even usable by...

    Provided By University of South Florida

  • White Papers // Oct 2009

    From Trees to DAGs: Improving the Performance of Bridged Ethernet Networks

    Ethernet is widely used in Local Area Networks (LANs) due to its simplicity and cost effectiveness. Today, a great deal of effort is being devoted to extending Ethernet capabilities in order to elevate it from a LAN technology to a ubiquitous networking technology, suitable for deployment in Metropolitan Area Networks...

    Provided By University of South Florida

  • White Papers // Oct 2009

    Adding Integrity Verification Capabilities to the LDPC-Staircase Erasure Correction Codes

    File distribution is becoming a key technology, in particular in large scale content broadcasting systems like DVBH/ SH. They largely rely on Application Level FEC codes (ALFEC) in order to recover from transmission erasures. The authors believe that sooner or later, content integrity and source authentication security services will be...

    Provided By University of South Florida

  • White Papers // Oct 2009

    Time-Varying FIR Decision Feedback Equalization for MIMO Transmission Over Doubly Selective Channels

    In this paper, the authors propose time-varying decision feedback FIR equalization techniques for Multiple-Input Multiple-Output (MIMO) transmission over doubly selective channels. The doubly selective channel is approximated using the Basis Expansion Model (BEM), and equalized by means of time-varying FIR filters. The time-varying FIR filters are modeled using the BEM....

    Provided By University of South Florida

  • White Papers // May 2012

    MQBM: An Autonomic QoS Multicast Routing Protocol for Mobile Ad Hoc Networks

    Mobile Ad hoc NETwork (MANET) is a wireless network that consists of a large number of mobile and heterogeneous nodes interconnected by wireless links which move in an arbitrary direction with random velocity. It is characterized by the absence of any pre-existing infrastructure. This makes the transmission more difficult especially,...

    Provided By University of South Florida

  • White Papers // Mar 2012

    Channel Quantization for Physical Layer Network-Coded Two-Way Relaying

    The design of modulation schemes for the physical layer network-coded two way relaying scenario is considered with the protocol which employs two phases: Multiple access (MA) Phase and Broadcast (BC) phase. It was observed by Koike-Akino et al. that adaptively changing the network coding map used at the relay according...

    Provided By University of South Florida

  • White Papers // Mar 2012

    On Spatial Load Balancing In Wide-Area Wireless Networks

    Load Balancing is typically used in cellular wireless networks in the frequency domain to balance paging, access, and traffic load across the available bandwidth. In this paper, the authors extend the concept of Load Balancing to the Spatial domain. They develop two approaches - Network Load Balancing and Single-Carrier MultiLink...

    Provided By University of South Florida

  • White Papers // Dec 2010

    Broadband Proximity Fed Modified E-Shaped Microstrip Antenna

    Commonly used technique to realize broadband microstrip antenna is by cutting the slots at an appropriate position inside the patch. The slot introduces a mode near the fundamental mode of the patch and yields broadband response. The bandwidth of an E-shaped microstrip antenna is further increased by cutting the pair...

    Provided By University of South Florida

  • White Papers // Dec 2010

    Generation of 60 GHz AM-PM Millimeter-Wave Signal Optically

    A scheme for the optical generation and modulation of mm-wave signal is proposed. The components required for the proposed mm-wave generator are an optical pulse source, a WDM demultiplexer, optical modulators and a wideband photodiode. Two coherent lightwaves are selected from the optical pulse and are modulated and then heterodyned...

    Provided By University of South Florida

  • White Papers // Dec 2010

    Mutual Information with Filterbank Equalization for MIMO Frequency Selective Channels

    The use of multiple antennas at both the transmitter and receiver is well motivated by the substantial performance gains that can be realized, both in terms of an increase in achievable data rate and a decrease in error rate. The achievable data rate is characterized by the mutual information of...

    Provided By University of South Florida

  • White Papers // Dec 2010

    An ICI Reduction Scheme with Enhanced Frequency Diversity for OFDM Systems

    The authors analyze the frequency diversity of InterCarrier Interference (ICI) reduction methods in the presence of phase noise over multipath fading channels. Based on analysis, they propose an Enhanced Symmetric Data Conjugate (ESDC) method to exploit the frequency diversity in multipath fading channel. They derive Carrier-to-Interference Ratio (CIR) expression of...

    Provided By University of South Florida

  • White Papers // Nov 2010

    Exact Error Analysis for Decode and Forward Cooperation with Maximal Ratio Combining

    In this paper, the authors provide exact expressions for the Bit Error Rate (BER) for single relay Maximal Ratio Combining (MRC) based Decode and Forward (DF) cooperative systems in Nakagami-m fading. This is done by expressing the decision variable as a sum of gamma Conditionally Gaussian (CG) random variables. The...

    Provided By University of South Florida

  • White Papers // Jan 2009

    Three-Stage Concatenated Ultra-Wide Bandwidth Time-Hopping Spread-Spectrum Impulse Radio Using Iterative Detection

    The powerful tool of EXtrinsic Information Transfer (EXIT) charts is used to design a new serially concatenated Irregular Variable Length Coded (IrVLC) and unity-rate precoded Time-Hopping (TH) Pulse Position Modulation (PPM) aided Ultra-Wide Bandwidth (UWB) Spread-Spectrum (SS) impulse radio for near-capacity operation in Nakagami-m fading channels contaminated by Partial Band...

    Provided By University of South Florida

  • White Papers // Dec 2009

    A New Diagonally Layered Spatial Multiplexing Scheme With Limited Feedback

    Multiple-Input Multiple-Output (MIMO) wireless systems, employing multiple transmit and receive antennas, promise significant improvement in the capacity compared to conventional Single-Input Single-Output (SISO) systems. It was shown that the capacity of MIMO wireless systems increases linearly with the minimum of the number of antennas at the transmitter and receiver in...

    Provided By University of South Florida

  • White Papers // Dec 2009

    Receiver-Only Optimized Vector Quantization for Fading Channels

    This paper considers the design and analysis of a filter at the receiver of a source coding system to mitigate the excess distortion caused due to channel errors. The index output by the source encoder is sent over a fading discrete binary symmetric channel and the possibly incorrect received index...

    Provided By University of South Florida

  • White Papers // Jan 2012

    Feasibility of Face Animation on Mobile Phones for Deaf Users

    Mobile telephone systems have made a fantastic progress in general, but deaf people are practically excluded from the benefits of mobiles. The authors' aim was to develop a new communication aid for deaf users. Their system directly converts the audio speech signal into the video of animated face, so the...

    Provided By University of South Florida

  • White Papers // Jan 2012

    Model-Based Trace-Checking

    Trace analysis can be a useful way to discover problems in a program under test. Rather than writing a special purpose trace analysis tool, this paper proposes that traces can usefully be analyzed by checking them against a formal model using a standard model-checker or else an animator for executable...

    Provided By University of South Florida

  • White Papers // May 2012

    First-Hop-Quality-Aware Dynamic Resource Allocation for Amplify-and-Forward Opportunistic Relaying Assisted SC-FDMA

    In this paper, the authors exploit the benefits of the diversity gains arising from a cluster of Opportunistic Relays (OR) and from the independently fading subcarriers of multiple users. Their goal is to improve the energy-efficiency of the OR assisted Single-Carrier Frequency-Division Multiple-Access (SC-FDMA) uplink using Amplify-and-Forward (AF), where the...

    Provided By University of South Florida

  • White Papers // May 2012

    Selective Relaying in Multi-Relay Networks With Feedback Delays and Adaptive Modulation

    This paper evaluates the performance of adaptive modulation in multi-relay networks with selective relaying, under Nakagami-m fading. In the system model, the source decides independently whether to forward the source message to the destination via the best (partial relay selection) relay path or direct path by comparing the end-to-end instantaneous...

    Provided By University of South Florida

  • White Papers // May 2012

    Relay Selection Schemes Relying on Adaptive Modulation and Imperfect Channel Knowledge for Cooperative Networks

    Cooperative MAC protocols have been shown to increase the attainable network throughput and to reduce the outage probability when perfect Channel State Information (CSI) is available either at the source station or at candidate relays. This paper investigates the realistically achievable network performance of relay selection schemes under imperfect CSI...

    Provided By University of South Florida

  • White Papers // May 2012

    Efficient Frequency Domain Packet Scheduler for Point-to-Multipoint Transmissions in LTE Networks

    Long Term Evolution (LTE) is the emerging 4G wireless technology developed to provide high quality services in mobile environments. It is foreseen that multimedia services and mobile TV will assume an important role for the LTE proliferation in mobile market. However, several issues are still open and meaningful improvements have...

    Provided By University of South Florida

  • White Papers // May 2012

    Efficient MIMO Antenna Evaluation Based on MIMO Spatial Channel Simulations

    This paper studies the proposal of using Spatial Channel Model (SCM) for the purpose of MIMO antenna parameter evaluation. The reason of choosing SCM is firstly explained. Then field measurements are conducted for comparison with simulations. The measurements have given preliminary proof to the applicability of the simulation method. To...

    Provided By University of South Florida

  • White Papers // May 2012

    A Novel Ergodic Capacity Analysis of Diversity Combining and Multihop Transmission Systems Over Generalized Composite Fading Channels

    Ergodic capacity is an important performance measure associated with reliable communication at the highest rate at which information can be sent over the channel with a negligible probability of error. In the shadow of this definition, diversity receivers (such as selection combining, equal-gain combining and maximal-ratio combining) and transmission techniques...

    Provided By University of South Florida

  • White Papers // May 2012

    Alternative Concepts of Antenna Deployment and Cell Layout in Mobile Communications

    Cellular communication systems have traditionally been designed according to the paradigm that base stations serve independent sectors for which inter-sector interference should be minimized. Further, multiple base stations serving multiple sectors are traditionally grouped into a minimum number of sites, in order to reuse infrastructure for cooling, battery backup etc....

    Provided By University of South Florida

  • White Papers // May 2012

    Truthful Auction for Cooperative Communications With Revenue Maximization

    Auction theory has been applied to cooperative communications to either efficiently allocate resources or incentivize wireless devices to participate in cooperative communications. However, a common shortcoming of the existing studies is that the revenue generation is neglected. Revenue generation is the ultimate goal of commercial networks, e.g., WiMAX networks. In...

    Provided By University of South Florida

  • White Papers // May 2012

    Characterizing Random CSMA Wireless Networks: A Stochastic Geometry Approach

    The authors characterize the random CSMA wireless networks by statistically quantifying the intensity of simultaneously active nodes and the aggregate interference experienced by a generic node in the network. First, starting from a Poisson point process to model the spatial distribution of the network nodes, they propose a Modified Hard...

    Provided By University of South Florida

  • White Papers // May 2012

    Modeling Random CSMA Wireless Networks in General Fading Environments

    Carrier-Sense Multiple Access (CSMA) protocols coordinate the spectrum access to maximize the spatial frequency reuse and minimize the mutual interference in distributed wireless networks. Since the CSMA protocol correlates the positions of the simultaneously active transmitters, the analytically tractable Poisson Point Process (PPP) cannot be used to model the spatial...

    Provided By University of South Florida

  • White Papers // Oct 2009

    The Impact of Mobility on OFDMA-Based Cellular Systems with Reuse Partitioning

    Reuse Partitioning has been recently proposed as an effective inter-cell interference mitigation strategy for OFDMA cellular networks. However, mobility of users has been largely ignored in the system level analysis of these systems. To fill this void, in this paper, a tele-traffic analysis of a Reuse Partitioning (RP) system is...

    Provided By University of South Florida