Beijing University of Posts and Telecommunications

Displaying 1-40 of 82 results

  • White Papers // Dec 2013

    Cloud Service-Aware Location Update in Mobile Cloud Computing

    Mobile devices are becoming the primary platforms for many users who always roam around when accessing the cloud computing services. From this, the cloud computing is integrated into the mobile environment by introducing a new paradigm, mobile cloud computing. In the context of mobile computing, the battery life of mobile...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jul 2013

    A Novel Dynamic Identity based Authentication Scheme for Multi-Server Environment using Smart Cards

    Remote user authentication scheme with key agreement is a very practical mechanism to verify a remote user and then provide secure communication. Furthermore, many network environments have been becoming multi-server based due to the rapid growth of computer networks. Therefore, more and more researches have been focused on proposing smart...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2013

    An Efficient Dynamic ID Based Remote User Authentication Scheme Using Self-Certified Public Keys for Multi-Server Environment

    Recently, Li et al. analyzed Lee et al.'s multi-server authentication scheme and proposed a novel smart card and dynamic ID based remote user authentication scheme for multi-server environments. They claimed that their scheme can resist several kinds of attacks. However, through careful analysis, the authors find that Li et al.'s...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Apr 2013

    An Anonymous User Authentication with Key Agreement Scheme Without Pairings for Multiserver Architecture Using SCPKs

    With advancement of computer community and widespread dissemination of network applications, users generally need multiple servers to provide different services. Accordingly, the multi-server architecture has been prevalent, and designing a secure and efficient remote user authentication under multi-server architecture becomes a nontrivial challenge. In last decade, various remote user authentication...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Apr 2013

    A Truthful and Low-Overhead Routing Protocol for Ad Hoc Networks

    Nodes in wireless ad hoc networks depend on others for forwarding packets hop by hop. However, nodes may behave selfishly and do not forward packets for saving their limited resources. Approaches based on Vickrey, Clarke and Groves (VCG) pay to the intermediate nodes a premium over their actual costs to...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Feb 2013

    Energy Sensing and Monitoring Framework with an Integrated Communication Backbone in Energy Efficient Intelligent Buildings

    Building environments are significant sources of global energy consumption. To create energy efficient buildings, the first step is to sense and monitor all the energy-consuming appliances in the buildings and record all the energy consumption information. After that, appropriate energy saving policies can be decided and the instructions can be...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Nov 2012

    A Novel Multi-Objective Relay-Jammer Pair Selection Scheme in Wireless Cooperative Networks

    To further enhance the Quality of Service (QoS), this paper proposes a novel multi-objective relay-jammer pair selection scheme in wireless cooperative networks where the wireless channels are modeled as first-order Finite-State Markov Channels (FSMCs). The FSMC model is used to approximate the time variations of the average received Signal-to-Noise Ratio...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Nov 2012

    Random Circulant Orthogonal Matrix Based Analog Compressed Sensing

    Analog Compressed Sensing (CS) has attracted considerable research interest in sampling area. One of the promising analog CS technique is the recently proposed Modulated Wideband Converter (MWC). However, MWC has a very high hardware complexity due to its parallel structure. To reduce the hardware complexity of MWC, this paper proposes...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Nov 2012

    Minimizing Electricity Cost in Geographical Virtual Network Embedding

    In light of rapid increase of electricity cost, many business organizations have to find new ways to cut the electricity bill. This paper studies how to reduce the electricity cost in geographical inter-domain virtual network embedding, which embeds virtual networks requested by users to multiple geographically distributed substrate networks run...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Nov 2012

    Topology-Aware Virtual Network Embedding Through Bayesian Network Analysis

    Multiple heterogeneous virtual networks are given the ability to run on a shared infrastructure simultaneously as independent slices in the network virtualization environment. However, a major challenge is how to map multiple virtual networks, with specific node and link constraints, onto the shared substrate network, known as virtual network embedding...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    Zero-Forcing Based MIMO Two-Way Relay With Relay Antenna Selection: Transmission Scheme and Diversity Analysis

    The combination of Physical-layer Network Coding (PNC) and Multiple-Input Multiple-Output (MIMO) is expected to improve the throughput of two-way relay network. In this paper, the authors propose a zero-forcing based MIMO two-way relay scheme in conjunction with a simple Max-Min relay antenna selection. This scheme solves the unpractical constraint encountered...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    Optimal Power Allocation and Relay Selection in Dual-Hop and Multi-Hop Cognitive Networks

    In this paper, the authors consider a cognitive relay network which contains a source node, a destination node and a group of network clusters each consisting of several cognitive relay nodes. They choose one relay node with the optimal power value in each cluster to aid the data transmission from...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    Spectrum Sharing and Resource Allocation for Energy-Efficient Heterogeneous Cognitive Radio Networks With Femtocells

    In heterogeneous wireless networks with femtocells, the issue of interference between femtocells and macrocells should be carefully considered. Using cognitive radio for interference management is a promising technique in heterogeneous wireless networks with femtocells. In this paper, the authors study the energy efficiency aspect of spectrum sharing and resource allocation...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    An Indirect Reciprocity Game Theoretic Framework for Dynamic Spectrum Access

    In this paper, the authors propose a spectrum access framework to address the efficient allocation of channels of a Base Station (BS) by stimulating cooperation between Primary Users (PUs) and Secondary Users (SUs). They model the cooperation stimulation problem as an indirect reciprocity game, where SUs help PUs relay information...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    Interference-Aware Resource Allocation in Co-Channel Deployment of OFDMA Femtocells

    Macrocells may suffer serious uplink interference introduced by the deployment of co-channel femtocells. In this paper, an interference-aware pricing-based resource allocation algorithm for co-channel femtocells is proposed to alleviate their interference to macrocells without degrading the femtocell's capacity. The subchannel and power allocation problem is modeled as a non-cooperative game....

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    Joint Time-Varying Channel Estimation With Dual-ICI Cancellation in OFDM Systems

    Channel estimation plays a vital role in coherent detection and demodulation in Orthogonal Frequency Division Multiplexing (OFDM) systems. However, the channel time-variation leads to tremendous unknown parameters to estimate and detrimental Inter-Carrier Interference (ICI) for pilot-aided channel estimation, degrading the system performance significantly. This paper proposes a joint estimation of...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    Hybrid Virtual Network Embedding With K-Core Decomposition and Time-Oriented Priority

    Network virtualization provides a powerful tool to allow multiple networks, each customized to a specific purpose, to run on a shared substrate. However, a big challenge is how to map multiple virtual networks onto specific nodes and links in the shared substrate network, known as virtual network embedding problem. Previous...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    Radio Admission Control Scheme for High-Speed Railway Communication With MIMO Antennas

    Along with the wide deployment of high-speed railway at more than 300 km/h, providing various services effectively for users in the train becomes both practical demand and interesting challenge for wireless communication. Due to the specific environment for high-speed railway, existing Radio Admission Control (RAC) algorithms could not suit the...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    TCP Performance Improvement in Wireless Networks With Cooperative Communications and Network Coding

    Cooperative communications and network coding are considered as effective technologies to provide robust and efficient communications. Most existing studies focus on lower layer performance, such as bandwidth efficiency, and little attention has been paid to the performance in the upper layers, such as Transmission Control Protocol (TCP) throughput. In this...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    A Novel Time Domain Approach for the Downlink Pilot Design of Multiantenna OFDM Systems

    A novel time domain approach is introduced for the downlink pilot design of multi-antenna OFDM systems. Zero correlation zone sequence sets are used to construct the pilot sequences so that the intra- and inter-cell interferences between pilots are cancelled. The pilot sequences are superimposed on the time domain data signals...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    A Novel Frame Structure for Centralized Cooperative Cognitive Networks to Achieve Overhead-Throughput Tradeoff

    With the rapid development of wireless communication networks, more and more spectrum resources are required and the scarcity in spectrum has become a serious concern. Cognitive Radio (CR) technology, which enables Secondary User (SU) to access the idle frequency bands known as the spectrum hole, has been proposed to improve...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    On the Performance of Opportunistic Amplify-and-Forward Relaying in Two-Wave With Diffuse Power Fading Channels

    This paper considers cooperative networks in independent and non-identical Two-Wave with Diffuse Power (TWDP) fading channels using opportunistic Amplify-and-Forward (AF) relaying. The authors derive new closed-form expressions for the outage probability and Symbol Error Rate (SER) in the high Signal-to-Noise Ratio (SNR) regime. Such expressions can be applied to opportunistic...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    System-Level Analysis and Evaluation of SF-DC Transmit Mode in HSPA+ System

    Cooperated multi-point technique in HSPA+ system has not been paid attention until the Single Frequency Dual Cell (SF-DC) mode, where one User Equipment (UE) may be served by dual Node-Bs simultaneously in the single carrier frequency network, is proposed recently. In the previous research, the system-level performance with SF-DC operation...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    Mobile Sensor Scheduling for Timely Sweep Coverage

    Mobile sensors are a viable choice for providing monitoring service on a set of Points of Interest (PoIs) in a large sensing field. In some applications, each PoI should be covered periodically (sweep coverage), and the collected data should be delivered to the sink node timely (timely transmission), namely both...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    Through-Wall Tracking With Radio Tomography Networks Using Foreground Detection

    This paper presents a novel method for tracking a moving person or object through walls using wireless networks. The method takes advantage of the motion-induced variation of Received Signal Strength (RSS) measurements in a radio tomography network. Based on real measurements of a deployed network, the authors show that the...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    Novel Recursive Approach for OFDM Channel Estimation Under Highly Mobile Conditions

    This paper proposes a novel recursive approach for Orthogonal Frequency Division Multiplexing (OFDM) channel estimation over highly mobile channels without any priori channel statistics. The key idea is to decompose each objective channel into the known component and the rest for estimation. The known component is the output of the...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    A Separate-SMDP Approximation Technique for RRM in Heterogeneous Wireless Networks

    This paper proposes the separate-SMDP approximation technique to solve the dimensionality problem of the Semi-Markov Decision Process (SMDP) model for Radio Resource Management (RRM). The proposed separate-SMDP model approximates the original complex SMDP Linear Programming (LP) problem by building a series of simple SMDP LP problems. The estimated policy results...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    A Physarum-Inspired Algorithm for Minimal Exposure Problem in Wireless Sensor Networks

    Exposure problem, which corresponds to the quality of coverage, is a fundamental problem in wireless sensor networks. In this paper, the authors exploit a cellular computing model in the physarum for solving the minimal exposure problem. They first use the road-network among all Points of Interesting (PoIs) in the monitoring...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    Collaborative Spectrum Sensing in Multi-Channel Cognitive Networks: A Coalition Game Approach

    Collaborative spectrum sensing among Secondary Users (SUs) in Cognitive Radio (CR) networks is shown to yield a significant performance improvement. However, much previous work in CR networks focus on single channel sensing performed by SU cooperatively while spectrum sensing on multiple channels is largely ignored. In order to overcome the...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    Distributed Cooperative Spectrum Sensing for Cognitive Radio Networks

    Spectrum sensing is an essential functionality of cognitive radio networks. In this paper, a non-cooperative game framework is proposed for studying the interactions between multiple secondary strategic users in spectrum sensing. The licensed spectrum of single primary user is divided into K sub-bands, each secondary user operates exclusively in one...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    A Distributed Algorithm Combining Power Control and Scheduling for Femtocell Networks

    In this paper, the authors present a distributed algorithm combining power control and scheduling for densely deployed femtocells networks. The strong interference in the downlink from the femtocells should be well mitigated to satisfy the Quality of Service (QoS) requirement of femtocell users. The considered optimization problem is formulated as...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    An Optimization Method for P2P Resource Scheduling

    Because the information exchange between peers of P2P application system is limited by the real network topology, effective resource scheduling technology becoming an important issue. Without change to peers' reciprocity and self-organization, an optimization method based on ant colony algorithm for P2P resource scheduling is proposed. The task of system...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    Forwarders Selection Mechanism Based on Packets Transmission Rate for Opportunistic Routing in Wireless Mesh Network

    In this paper, a novel routing metric TRE (Transmission Rate based on EEPEST (End-to-End Probability of Effective Successful Transmission)) is proposed to choose the forwarder list, which is based on total effective successful transmission rate. It considers multi-links contribution, instead of one "Best" link information used in ETX. The extensive...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Feb 2012

    Energy-Aware Combinatorial Scheduling in Cloud Datacenter

    Cloud Computing is evolving as a key computing platform for sharing resources that include infrastructures, software, applications, and business processes. As the scale of cloud datacenter becomes larger and larger, how to reduce energy consumption in large-scale datacenters become a big problem to resolve as soon as possible. How to...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Feb 2012

    Unified Authentication Scheme Based on IBE in Trusted Network

    The existing unified authentication schemes are based on Public Key Infrastructure (PKI)/Privilege Management Infrastructure (PMI), WS-Security, Kerberos etc. But they can't support the developing Trusted Network Connect (TNC) environment. To solve the problem, a unified authentication scheme supporting multi-authentication modes based on Identity-Based Encryption (IBE) in trusted network named IEUAS...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Feb 2012

    A Novel Analytical Model for IEEE802.11e WLANs With 3-D Markov Chain

    IEEE 802.11e is specified to provide prioritized Quality of Service (QoS) guarantee in Wireless Local Area Networks (WLANs). A comprehensive investigation of the performance of Enhanced Distributed Channel Access (EDCA) for WLANs is reported in this paper. Most of the previous related paper is based on saturation condition which is...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jan 2012

    Energy-Efficient Spectrum Sharing and Power Allocation in Cognitive Radio Femto-cell Networks

    Both cognitive radio and femtocell have been considered as promising techniques in wireless networks. However, most of previous works are focused on spectrum sharing and interference avoidance, and the energy efficiency aspect is largely ignored. In this paper, the authors study the energy efficiency aspect of spectrum sharing and power...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jan 2012

    New Cloud Computing Network Architecture Directed At Multimedia

    Multimedia computing has caused increasing resource consumption and computational overhead. This paper pays its considerable attention to cloud computing in handling multimedia applications and services effectively and efficiently. The authors present a solution to reconstruct the network architecture of multimedia field based on cloud computing to integrate multi-service platforms for...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jan 2012

    Energy-Aware and Revenue-Enhancing Combinatorial Scheduling in Virtualized of Cloud Datacenter

    As the scale of cloud datacenter becomes larger and larger, the energy consumption and revenue enhancing of the cloud datacenter will grow rapidly. How to improve high-throughput computing resource allocation strategy was taken into account. High-throughput computing resource consolidation is an effective method to increase resource utilization and in turn...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Dec 2011

    Analysis and Improvement of a Strongly Secure Certificateless Key Exchange Protocol Without Pairing

    Recently, Yang and Tan proposed a certificate less key exchange protocol without pairing, and claimed their scheme satisfies forward secrecy, which means no adversary could derive an already-established session key unless the full user secret keys (including a private key and an ephemeral secret key) of both communication parties are...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2011

    Fixed Relay Random Access Protocol for Cooperative Network

    This paper presents a fixed relay nodes random access protocol which based on time division multiple access. The protocol uses the users and relay nodes cooperation retransmission mechanism to solve the multi-user access collision problem. The key idea is to use non-persistent monitor way for random access, guarantee a certain...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jun 2011

    A Novel Supernodes Election Scheme in Structured P2P Network

    Most Peer-To-Peer (P2P) applications need to elect some SuperNodes (SNs) from ordinary nodes to improve their performance. So, SuperNodes election has become an important issue in such systems. However, choosing the best SNs is not a trivial problem from a huge and dynamically changing P2P environment. The random election strategy...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Oct 2011

    An HVS-Based JPEG Image Watermarking Method for Copyright Protection

    A practical watermarking method for the copyright protection of JPEG image is proposed in this paper. By operating the pixel matrix of depressed the JPEG image, the authors can use the DCT coefficients to embed the watermark. The strength of watermark can be controlled by visual masking and analysis of...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Oct 2011

    Reduce-Reference Transmission-Aware Video Quality Metric for MPEG-4 Encoded Videos Over Lossy Wireless Network

    In previous studies, Just Noticeable Distortion (JND) is proved as the most suitable index to reflect the videos' content natures. Meanwhile, transmission parameters are the major impact factors to the video quality degradation under unstable wireless networks. Therefore, the authors propose a reduce-reference Transmission-aware Quality Metric (TQM) for real-time quality...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Nov 2011

    Optimized Superimposed Training Aided Linear Time-Varying Channel Estimation Model for OFDM Systems

    The authors propose an optimized time-varying channel estimation model for mobile Orthogonal Frequency Division Multiplexing (OFDM) systems applying superimposed training in time domain to assist the channel estimation. An extension line approximate method is proposed to fit the assumed linear time-varying channel. The performance of the proposed method is compared...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Dec 2011

    A Novel Iterative Algorithm for Time-Varying Channel Estimation in OFDM Systems

    A novel iterative channel estimation algorithm for Orthogonal Frequency-Division Multiplexing (OFDM) systems in fast time-varying environment is proposed. Instead of directly estimate the original channel taps, the proposed estimation focus on the rest channel part from the original channel taps subtracted by the prior estimation results in the absence of...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jul 2009

    GTPP: General Truncated Pyramid Peer-to-Peer Architecture

    Hierarchical Distributed Hash Table (DHT) architectures have been among the most interesting research topics since the birth of flat DHT architecture. However, most of the previous work has merely focused on the two-tier hierarchy. In this paper, the authors study and analyze General Truncated Pyramid Peer-to-Peer (GTPP) architecture, the generalized...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jan 2012

    Energy-Efficient Spectrum Sharing and Power Allocation in Cognitive Radio Femto-cell Networks

    Both cognitive radio and femtocell have been considered as promising techniques in wireless networks. However, most of previous works are focused on spectrum sharing and interference avoidance, and the energy efficiency aspect is largely ignored. In this paper, the authors study the energy efficiency aspect of spectrum sharing and power...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Apr 2010

    Location Optimization for Decode-and-Forward Opportunistic Cooperative Networks

    In this paper, the authors investigate the location optimization for Decode-and-Forward (DF) opportunistic cooperative networks, in which the impact of the availability of the direct link between the source and the destination has been studied. Under Rayleigh fading channels, the closed-form solution for the optimal location is derived. It is...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Apr 2010

    Limited Feedback Scheme Based on Zero-Forcing Precoding for Multiuser MIMO-OFDM Downlink Systems

    Conventional zero-forcing precoding was well investigated, but it hadn't considered the Channel Quality Indicator (CQI) mismatch for practical system with limited feedback. This paper studies a novel zero-forcing precoding with Channel Quality Indicator (CQI) estimation and adjusting, Channel Directional Information (CDI) quantization, user scheduling and link adaptation and then proposes...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    Zero-Forcing Based MIMO Two-Way Relay With Relay Antenna Selection: Transmission Scheme and Diversity Analysis

    The combination of Physical-layer Network Coding (PNC) and Multiple-Input Multiple-Output (MIMO) is expected to improve the throughput of two-way relay network. In this paper, the authors propose a zero-forcing based MIMO two-way relay scheme in conjunction with a simple Max-Min relay antenna selection. This scheme solves the unpractical constraint encountered...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    Optimal Power Allocation and Relay Selection in Dual-Hop and Multi-Hop Cognitive Networks

    In this paper, the authors consider a cognitive relay network which contains a source node, a destination node and a group of network clusters each consisting of several cognitive relay nodes. They choose one relay node with the optimal power value in each cluster to aid the data transmission from...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    Spectrum Sharing and Resource Allocation for Energy-Efficient Heterogeneous Cognitive Radio Networks With Femtocells

    In heterogeneous wireless networks with femtocells, the issue of interference between femtocells and macrocells should be carefully considered. Using cognitive radio for interference management is a promising technique in heterogeneous wireless networks with femtocells. In this paper, the authors study the energy efficiency aspect of spectrum sharing and resource allocation...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    An Indirect Reciprocity Game Theoretic Framework for Dynamic Spectrum Access

    In this paper, the authors propose a spectrum access framework to address the efficient allocation of channels of a Base Station (BS) by stimulating cooperation between Primary Users (PUs) and Secondary Users (SUs). They model the cooperation stimulation problem as an indirect reciprocity game, where SUs help PUs relay information...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    Interference-Aware Resource Allocation in Co-Channel Deployment of OFDMA Femtocells

    Macrocells may suffer serious uplink interference introduced by the deployment of co-channel femtocells. In this paper, an interference-aware pricing-based resource allocation algorithm for co-channel femtocells is proposed to alleviate their interference to macrocells without degrading the femtocell's capacity. The subchannel and power allocation problem is modeled as a non-cooperative game....

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    Joint Time-Varying Channel Estimation With Dual-ICI Cancellation in OFDM Systems

    Channel estimation plays a vital role in coherent detection and demodulation in Orthogonal Frequency Division Multiplexing (OFDM) systems. However, the channel time-variation leads to tremendous unknown parameters to estimate and detrimental Inter-Carrier Interference (ICI) for pilot-aided channel estimation, degrading the system performance significantly. This paper proposes a joint estimation of...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    Hybrid Virtual Network Embedding With K-Core Decomposition and Time-Oriented Priority

    Network virtualization provides a powerful tool to allow multiple networks, each customized to a specific purpose, to run on a shared substrate. However, a big challenge is how to map multiple virtual networks onto specific nodes and links in the shared substrate network, known as virtual network embedding problem. Previous...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    Radio Admission Control Scheme for High-Speed Railway Communication With MIMO Antennas

    Along with the wide deployment of high-speed railway at more than 300 km/h, providing various services effectively for users in the train becomes both practical demand and interesting challenge for wireless communication. Due to the specific environment for high-speed railway, existing Radio Admission Control (RAC) algorithms could not suit the...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    TCP Performance Improvement in Wireless Networks With Cooperative Communications and Network Coding

    Cooperative communications and network coding are considered as effective technologies to provide robust and efficient communications. Most existing studies focus on lower layer performance, such as bandwidth efficiency, and little attention has been paid to the performance in the upper layers, such as Transmission Control Protocol (TCP) throughput. In this...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    A Novel Time Domain Approach for the Downlink Pilot Design of Multiantenna OFDM Systems

    A novel time domain approach is introduced for the downlink pilot design of multi-antenna OFDM systems. Zero correlation zone sequence sets are used to construct the pilot sequences so that the intra- and inter-cell interferences between pilots are cancelled. The pilot sequences are superimposed on the time domain data signals...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2012

    A Novel Frame Structure for Centralized Cooperative Cognitive Networks to Achieve Overhead-Throughput Tradeoff

    With the rapid development of wireless communication networks, more and more spectrum resources are required and the scarcity in spectrum has become a serious concern. Cognitive Radio (CR) technology, which enables Secondary User (SU) to access the idle frequency bands known as the spectrum hole, has been proposed to improve...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    On the Performance of Opportunistic Amplify-and-Forward Relaying in Two-Wave With Diffuse Power Fading Channels

    This paper considers cooperative networks in independent and non-identical Two-Wave with Diffuse Power (TWDP) fading channels using opportunistic Amplify-and-Forward (AF) relaying. The authors derive new closed-form expressions for the outage probability and Symbol Error Rate (SER) in the high Signal-to-Noise Ratio (SNR) regime. Such expressions can be applied to opportunistic...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    System-Level Analysis and Evaluation of SF-DC Transmit Mode in HSPA+ System

    Cooperated multi-point technique in HSPA+ system has not been paid attention until the Single Frequency Dual Cell (SF-DC) mode, where one User Equipment (UE) may be served by dual Node-Bs simultaneously in the single carrier frequency network, is proposed recently. In the previous research, the system-level performance with SF-DC operation...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    Mobile Sensor Scheduling for Timely Sweep Coverage

    Mobile sensors are a viable choice for providing monitoring service on a set of Points of Interest (PoIs) in a large sensing field. In some applications, each PoI should be covered periodically (sweep coverage), and the collected data should be delivered to the sink node timely (timely transmission), namely both...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    Through-Wall Tracking With Radio Tomography Networks Using Foreground Detection

    This paper presents a novel method for tracking a moving person or object through walls using wireless networks. The method takes advantage of the motion-induced variation of Received Signal Strength (RSS) measurements in a radio tomography network. Based on real measurements of a deployed network, the authors show that the...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    Novel Recursive Approach for OFDM Channel Estimation Under Highly Mobile Conditions

    This paper proposes a novel recursive approach for Orthogonal Frequency Division Multiplexing (OFDM) channel estimation over highly mobile channels without any priori channel statistics. The key idea is to decompose each objective channel into the known component and the rest for estimation. The known component is the output of the...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    A Separate-SMDP Approximation Technique for RRM in Heterogeneous Wireless Networks

    This paper proposes the separate-SMDP approximation technique to solve the dimensionality problem of the Semi-Markov Decision Process (SMDP) model for Radio Resource Management (RRM). The proposed separate-SMDP model approximates the original complex SMDP Linear Programming (LP) problem by building a series of simple SMDP LP problems. The estimated policy results...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    A Physarum-Inspired Algorithm for Minimal Exposure Problem in Wireless Sensor Networks

    Exposure problem, which corresponds to the quality of coverage, is a fundamental problem in wireless sensor networks. In this paper, the authors exploit a cellular computing model in the physarum for solving the minimal exposure problem. They first use the road-network among all Points of Interesting (PoIs) in the monitoring...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    Collaborative Spectrum Sensing in Multi-Channel Cognitive Networks: A Coalition Game Approach

    Collaborative spectrum sensing among Secondary Users (SUs) in Cognitive Radio (CR) networks is shown to yield a significant performance improvement. However, much previous work in CR networks focus on single channel sensing performed by SU cooperatively while spectrum sensing on multiple channels is largely ignored. In order to overcome the...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2012

    Distributed Cooperative Spectrum Sensing for Cognitive Radio Networks

    Spectrum sensing is an essential functionality of cognitive radio networks. In this paper, a non-cooperative game framework is proposed for studying the interactions between multiple secondary strategic users in spectrum sensing. The licensed spectrum of single primary user is divided into K sub-bands, each secondary user operates exclusively in one...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Nov 2012

    A Novel Multi-Objective Relay-Jammer Pair Selection Scheme in Wireless Cooperative Networks

    To further enhance the Quality of Service (QoS), this paper proposes a novel multi-objective relay-jammer pair selection scheme in wireless cooperative networks where the wireless channels are modeled as first-order Finite-State Markov Channels (FSMCs). The FSMC model is used to approximate the time variations of the average received Signal-to-Noise Ratio...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Nov 2012

    Random Circulant Orthogonal Matrix Based Analog Compressed Sensing

    Analog Compressed Sensing (CS) has attracted considerable research interest in sampling area. One of the promising analog CS technique is the recently proposed Modulated Wideband Converter (MWC). However, MWC has a very high hardware complexity due to its parallel structure. To reduce the hardware complexity of MWC, this paper proposes...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Nov 2012

    Minimizing Electricity Cost in Geographical Virtual Network Embedding

    In light of rapid increase of electricity cost, many business organizations have to find new ways to cut the electricity bill. This paper studies how to reduce the electricity cost in geographical inter-domain virtual network embedding, which embeds virtual networks requested by users to multiple geographically distributed substrate networks run...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Nov 2012

    Topology-Aware Virtual Network Embedding Through Bayesian Network Analysis

    Multiple heterogeneous virtual networks are given the ability to run on a shared infrastructure simultaneously as independent slices in the network virtualization environment. However, a major challenge is how to map multiple virtual networks, with specific node and link constraints, onto the shared substrate network, known as virtual network embedding...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Feb 2011

    Mobile Wireless Sensor Networks: Architects for Pervasive Computing

    A mobile wireless sensor network owes its name to the presence of mobile sink or sensor nodes within the network. The advantages of mobile wireless sensor network over static wireless sensor network are better energy efficiency, improved coverage, enhanced target tracking and superior channel capacity. In this paper, the authors...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Oct 2009

    An Efficient Parallel Algorithm with Partial Decision Feedback for Near-Optimal MIMO Detection

    Maximum-Likelihood Detection (MLD) is the optimal scheme for Multiple-Input Multiple-Output (MIMO) channels. However, due to its exponentially high complexity, many alternative algorithms, including some Parallel Detection (PD) ones with low complexity and high stability, have been proposed for practical applications. Nevertheless, the existing PD algorithms are unable to exploit sufficiently...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Oct 2009

    A Novel Observe-and-Forward Scheme in Wireless Cooperative Relaying Systems

    In this paper, a novel Observe-and-Forward (OF) cooperative scheme is proposed for relay-enhanced wireless cooperative systems. In this scheme, the codewords transmitted from the source are regenerated by the decoder at the relay and forwarded without re-encoding or interleaving. The decoding processes for different streams of a transmitted codeword can...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Apr 2013

    A Truthful and Low-Overhead Routing Protocol for Ad Hoc Networks

    Nodes in wireless ad hoc networks depend on others for forwarding packets hop by hop. However, nodes may behave selfishly and do not forward packets for saving their limited resources. Approaches based on Vickrey, Clarke and Groves (VCG) pay to the intermediate nodes a premium over their actual costs to...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Sep 2011

    A New Architecture of HSS Based on Cloud Computing

    IP Multimedia Subsystem (IMS) is the key technology of the Next Generation Network (NGN) and the optimal solution of mobile and fixed network convergence which is approved by the public. Home Subscribe Server (HSS) is not only the data center of the system, but also the key of supporting the...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // May 2013

    An Efficient Dynamic ID Based Remote User Authentication Scheme Using Self-Certified Public Keys for Multi-Server Environment

    Recently, Li et al. analyzed Lee et al.'s multi-server authentication scheme and proposed a novel smart card and dynamic ID based remote user authentication scheme for multi-server environments. They claimed that their scheme can resist several kinds of attacks. However, through careful analysis, the authors find that Li et al.'s...

    Provided By Beijing University of Posts and Telecommunications