Beijing University of Posts and Telecommunications

Displaying 41-80 of 81 results

  • 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 // 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 // Oct 2011

    Multi-User Scheduling for Network Coded Two-Way Relay Channel in Cellular Systems

    There has been a growing interest on analog network coding which can improve system throughput and spectrum efficiency significantly in wireless systems. Two-way relay scenario is considered in the paper, where the Base Station (BS) and the relay are both equipped with multiple antennas, and each of K User Equipments...

    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 // 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 // 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 // Jun 2011

    Self-Aware Services of NGSDP:Using Bayesian Networks for Measuring Quality of Convergent Services

    The authors propose a general architecture and implementation for the autonomous assessment of quality of arbitrary service elements in the convergent service environments. They describe a quality engine, which is the central component of the proposed architecture of self-aware convergent services of NGSDP. The quality engine combines domain independent statistical...

    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 // Mar 2011

    A New Secure Strategy in Small-Scale IEEE 802.11 Wireless Local Area Networks With Web Authentication and Virtual Local Area Network

    As the main secret-key encryption techniques of the Wireless Local Area Network (WLAN) have been proven to be unsafe, wireless network security is faced with serious challenges. It is unpractical for home users and small companies to purchase expensive network equipments to improve the network security. Therefore, the secure strategy...

    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 // Feb 2011

    K-Means Based Clustering on Mobile Usage for Social Network Analysis Purpose

    The development of mobile network technology provides a great potential for social networking services. This paper studied data mining for social network analysis purpose, which aims at find people's social network patterns by analyzing the information about their mobile phone usage. In this research, the real database of MIT's Reality...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Feb 2011

    A Novel Virtual Network Mapping Algorithm for Cost Minimizing

    Resources assigned to virtual network are not optimal resources, which are caused by some scarce resources. To solve this problem, this paper proposes a novel virtual network mapping algorithm that can realize mapping cost minimizing, called CMVNMA, based on two characteristics of network virtualization environment that is virtual network has...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Feb 2011

    Improved Performance of the Basic Array of a Microstrip Adaptive Antenna Using a Tree Structure of Patch Fed by Electromagnetic Coupling

    The aim of this paper is to improve the performance of a basic microstrip antenna array using a tree structure patch supplied by electromagnetic coupling. The developed network which contains two subnets, a distribution subnet and a scanning subnet, is considered as a first step to design an adaptive microstrip...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Feb 2011

    UWB Channel Estimation Based on Distributed Bayesian Compressive Sensing

    In order to solve the high sampling rate issue in the multiuser UWB communication network system, the authors process the received signal with Bayesian compressive sensing. Using the characteristic that the wireless channels of multiuser signals which are received by one receiver at the same time are statistically related, a...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jan 2011

    Supernode Election Algorithm in P2P Network Based Upon District Partition

    Nowadays the idea of Peer-To-Peer (P2P) has been used in many fields, such as file sharing, cooperative processing, information sharing and communication etc. According to the definition, the Peer-To-Peer (P2P) network is a type of Internet network allowing a group of computer users with the same networking program to connect...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Dec 2010

    Impact of Deployment Size on the Asymptotic Capacity for Wireless Ad Hoc Networks Under Gaussian Channel Model

    In this paper, the authors studied the impact of the size of the deployment region on the asymptotic unicast and multicast throughput capacity for wireless networks under Gaussian channel model. They derived asymptotic matching upper-bounds and lower-bounds of unicast capacity for arbitrary and random wireless networks in different cases. Their...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Nov 2010

    A Selection Region Based Routing Protocol for Random Mobile Ad Hoc Networks With Directional

    In this paper, the authors propose a selection region based multihop routing protocol with directional antennas for wireless mobile ad hoc networks, where the selection region is defined by two parameters: a reference distance and the beamwidth of the directional antenna. At each hop, they choose the nearest node to...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Sep 2010

    Downlink Scheduling and Radio Resource Allocation in Adaptive OFDMA Wireless Communication Systems for User-Individual QoS

    In this paper, the authors address the problem of adaptive Radio Resource Allocation (RRA) and packet scheduling in the downlink of a cellular OFDMA system, and propose a downlink Multi-carrier Proportional Fair (MPF) scheduler and its joint with adaptive RRA algorithm to distribute radio resources among multiple users according to...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Sep 2010

    Joint Uplink and Downlink Relay Selection in Cooperative Cellular Networks

    The authors consider relay selection technique in a cooperative cellular network where user terminals act as mobile relays to help the communications between Base Station (BS) and mobile station (MS). A novel relay selection scheme, called Joint Uplink and Downlink Relay Selection (JUDRS), is proposed in this paper. Specifically, they...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Sep 2010

    A Priority and SDB Based Admission Control in IEEE 802.16 Systems

    In IEEE 802.16 systems, the algorithm of Admission Control (AC) is very important in guaranteeing the Quality of Service (QoS) and managing service flows. However, the IEEE 802.16 standards do not specify any related strategies or algorithms on AC. In order to improve the system performance and satisfy the QoS...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Sep 2010

    Energy-Efficient Transmission Schemes in Cooperative Cellular Systems

    Energy-efficient communication is an important requirement for mobile devices, as the battery technology has not kept up with the growing requirements stemming from ubiquitous multimedia applications. This paper considers energy-efficient transmission schemes in cooperative cellular systems with unbalanced traffic between uplink and downlink. Theoretically, the authors derive the optimal transmission...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Aug 2010

    An Energy-Efficient Virtual MIMO Transmission Scheme for Cluster-Based Wireless Sensor Networks

    In this paper, a cluster-based virtual Multiple-Input Multiple-Output (MIMO) transmission scheme is proposed for energy-constrained wireless sensor networks. Compared with previous work, there are two new aspects in this scheme. Firstly, the proposed scheme makes use of multiple cluster heads cooperative transmission instead of one. Secondly, the Space-Time Block Coding...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Aug 2010

    Design and Analysis of a Hash Ring-Iterative Structure

    The authors propose a new type of hash iterative structure - the ring-iterative structure with feedback which is subdivided into the Single Feedback Ring Iteration and the Multiple Feedback Ring Iteration, namely SFRI and MFRI. Prove that SFRI is at least equivalent to the MD structure in security, and MFRI...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jul 2010

    Enhanced IMS Handoff Mechanism for QoS Support Over Heterogeneous Network

    IP Multimedia Subsystem (IMS) is over IP network architecture, but mobile IP cannot directly support session mobility controlled by session initiation protocol-based signaling. The long signaling delay for session reestablishment in application layer always results in session interruptions during the handoff. Therefore, handoff poses a challenge for Quality of Service...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jun 2010

    The Design and Implementation of Manual Task Customization in Workflow System Based on SaaS

    A workflow system for SaaS enables organizations of any size to build, execute, manage, and evolve its own process-oriented business applications. In this paper, the authors bring up a flexible manual task process customization workflow system based on SaaS to resolve the problems problem caused by orchestrating SaaS business process...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jun 2010

    Interference Mitigation for Coexistence of Heterogeneous Ultra-Wideband Systems

    Two Ultra-WideBand (UWB) specifications, that is, Direct-Sequence (DS) UWB and MultiBand-Orthogonal Frequency Division Multiplexing (MB-OFDM) UWB, have been proposed as the candidates of the IEEE 802.15.3a, competing for the standard of high-speed Wireless Personal Area Networks (WPAN). Due to the withdrawal of the standardization process, the two heterogeneous UWB technologies...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Apr 2010

    Energy-Efficient Relay Selection and Optimal Relay Location in Cooperative Cellular Networks With Asymmetric Traffic

    Energy-efficient communication is an important requirement for mobile relay networks due to the limited battery power of user terminals. This paper considers energy-efficient relaying schemes through selection of mobile relays in cooperative cellular systems with asymmetric traffic. The total energy consumption per information bit of the battery-powered terminals, i.e., the...

    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 // Feb 2010

    Efficient Access Control of Sensitive Data Service in Outsourcing Scenarios

    With the rapid application of service-oriented technologies, service and data outsourcing has become a practical and useful computing paradigm. Combined use of access control and cryptography was proposed by many researchers to protect information in this outsourcing scenario. However, existing approaches often limit dynamical update of access control policy, or...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Feb 2010

    Investigation of Cooperation Technologies in Heterogeneous Wireless Networks

    Heterogeneous wireless networks based on varieties of Radio Access Technologies (RATs) and standards will coexist in the future. In order to exploit this potential multiaccess gain, it is required that different RATs are managed in a cooperative fashion. This paper proposes two advanced functional architecture supporting the functionalities of interworking...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jan 2010

    Telecommunication Would Deliver More Managed Services for SMEs: Trends and Prosperity

    Small and Medium Enterprises (SMEs) find running business troublesome not only for improving core competitiveness, but also in the aspect of taking care of IT infrastructure. However, seemingly they cannot get the expected results due to the lack of IT specialists. On the other hand, with the substitution effect of...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jan 2010

    Enhanced MILSA Architecture for Naming, Addressing, Routing and Security Issues in the Next Generation Internet

    MILSA (Mobility and Multihoming supporting Identifier Locator Split Architecture) has been proposed to address the naming and addressing challenges for NGI (Next Generation Internet). The authors present several design enhancements for MILSA which include a hybrid architectural design that combines "Core-edge separation approach" and "Split approach", a security-enabled and logically...

    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 // Oct 2009

    Group CRM: A New Telecom CRM Framework From Social Network Perspective

    The structure of customer communication network provides a natural way to understand customers' relationships. Traditional customer relationship management (CRM) methods focus on various customer profitability models, and they are short of ways to understand the social interactions. Graph mining and social network analysis provide ways to understand the relationships between...

    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 // Jun 2009

    A General Stochastic Spatial MIMO Channel Model for Evaluating Various MIMO Techniques

    A general stochastic spatial MIMO channel model is proposed for evaluating various MIMO techniques in this paper. It can generate MIMO channels complying with various MIMO configurations such as smart antenna, spatial diversity and spatial multiplexing. The modeling method produces the stochastic fading involving delay spread, Doppler spread, DOA (Direction...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jun 2009

    New Birthday Attacks on Some MACs Based on Block Ciphers

    Message Authentication Code (MAC) is a fixed length information used to en-sure data integrity and authenticity, and is widely used in network and security protocols, such as IPSec, SNMP, and SSL/TLS. This paper develops several new techniques of cryptanalyzing MACs based on block ciphers, and is divided into two parts....

    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 // Oct 2011

    Multi-User Scheduling for Network Coded Two-Way Relay Channel in Cellular Systems

    There has been a growing interest on analog network coding which can improve system throughput and spectrum efficiency significantly in wireless systems. Two-way relay scenario is considered in the paper, where the Base Station (BS) and the relay are both equipped with multiple antennas, and each of K User Equipments...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jun 2010

    The Design and Implementation of Manual Task Customization in Workflow System Based on SaaS

    A workflow system for SaaS enables organizations of any size to build, execute, manage, and evolve its own process-oriented business applications. In this paper, the authors bring up a flexible manual task process customization workflow system based on SaaS to resolve the problems problem caused by orchestrating SaaS business process...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Oct 2009

    Group CRM: A New Telecom CRM Framework From Social Network Perspective

    The structure of customer communication network provides a natural way to understand customers' relationships. Traditional customer relationship management (CRM) methods focus on various customer profitability models, and they are short of ways to understand the social interactions. Graph mining and social network analysis provide ways to understand the relationships between...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Feb 2010

    Efficient Access Control of Sensitive Data Service in Outsourcing Scenarios

    With the rapid application of service-oriented technologies, service and data outsourcing has become a practical and useful computing paradigm. Combined use of access control and cryptography was proposed by many researchers to protect information in this outsourcing scenario. However, existing approaches often limit dynamical update of access control policy, or...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Nov 2010

    A Selection Region Based Routing Protocol for Random Mobile Ad Hoc Networks With Directional

    In this paper, the authors propose a selection region based multihop routing protocol with directional antennas for wireless mobile ad hoc networks, where the selection region is defined by two parameters: a reference distance and the beamwidth of the directional antenna. At each hop, they choose the nearest node to...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Sep 2010

    Joint Uplink and Downlink Relay Selection in Cooperative Cellular Networks

    The authors consider relay selection technique in a cooperative cellular network where user terminals act as mobile relays to help the communications between Base Station (BS) and mobile station (MS). A novel relay selection scheme, called Joint Uplink and Downlink Relay Selection (JUDRS), is proposed in this paper. Specifically, they...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Apr 2010

    Energy-Efficient Relay Selection and Optimal Relay Location in Cooperative Cellular Networks With Asymmetric Traffic

    Energy-efficient communication is an important requirement for mobile relay networks due to the limited battery power of user terminals. This paper considers energy-efficient relaying schemes through selection of mobile relays in cooperative cellular systems with asymmetric traffic. The total energy consumption per information bit of the battery-powered terminals, i.e., the...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Nov 2008

    Joint Transmitter-Receiver Design for the Downlink Multiuser Spatial Multiplexing MIMO System

    In the multiuser spatial multiplexing Multiple-Input Multiple-Output (MIMO) system, the joint Transmitter-Receiver (Tx-Rx) design is investigated to minimize the weighted sum power under the post-processing Signal-to-Interference-and-Noise Ratio (post-SINR) constraints for all subchannels. Firstly, the authors show that the uplink-downlink duality is equivalent to the Lagrangian duality in the optimization problems....

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jan 2010

    Enhanced MILSA Architecture for Naming, Addressing, Routing and Security Issues in the Next Generation Internet

    MILSA (Mobility and Multihoming supporting Identifier Locator Split Architecture) has been proposed to address the naming and addressing challenges for NGI (Next Generation Internet). The authors present several design enhancements for MILSA which include a hybrid architectural design that combines "Core-edge separation approach" and "Split approach", a security-enabled and logically...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Aug 2010

    Design and Analysis of a Hash Ring-Iterative Structure

    The authors propose a new type of hash iterative structure - the ring-iterative structure with feedback which is subdivided into the Single Feedback Ring Iteration and the Multiple Feedback Ring Iteration, namely SFRI and MFRI. Prove that SFRI is at least equivalent to the MD structure in security, and MFRI...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jun 2009

    A General Stochastic Spatial MIMO Channel Model for Evaluating Various MIMO Techniques

    A general stochastic spatial MIMO channel model is proposed for evaluating various MIMO techniques in this paper. It can generate MIMO channels complying with various MIMO configurations such as smart antenna, spatial diversity and spatial multiplexing. The modeling method produces the stochastic fading involving delay spread, Doppler spread, DOA (Direction...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Sep 2010

    A Priority and SDB Based Admission Control in IEEE 802.16 Systems

    In IEEE 802.16 systems, the algorithm of Admission Control (AC) is very important in guaranteeing the Quality of Service (QoS) and managing service flows. However, the IEEE 802.16 standards do not specify any related strategies or algorithms on AC. In order to improve the system performance and satisfy the QoS...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Mar 2011

    A New Secure Strategy in Small-Scale IEEE 802.11 Wireless Local Area Networks With Web Authentication and Virtual Local Area Network

    As the main secret-key encryption techniques of the Wireless Local Area Network (WLAN) have been proven to be unsafe, wireless network security is faced with serious challenges. It is unpractical for home users and small companies to purchase expensive network equipments to improve the network security. Therefore, the secure strategy...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jun 2011

    Self-Aware Services of NGSDP:Using Bayesian Networks for Measuring Quality of Convergent Services

    The authors propose a general architecture and implementation for the autonomous assessment of quality of arbitrary service elements in the convergent service environments. They describe a quality engine, which is the central component of the proposed architecture of self-aware convergent services of NGSDP. The quality engine combines domain independent statistical...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Feb 2011

    A Novel Virtual Network Mapping Algorithm for Cost Minimizing

    Resources assigned to virtual network are not optimal resources, which are caused by some scarce resources. To solve this problem, this paper proposes a novel virtual network mapping algorithm that can realize mapping cost minimizing, called CMVNMA, based on two characteristics of network virtualization environment that is virtual network has...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Feb 2011

    Improved Performance of the Basic Array of a Microstrip Adaptive Antenna Using a Tree Structure of Patch Fed by Electromagnetic Coupling

    The aim of this paper is to improve the performance of a basic microstrip antenna array using a tree structure patch supplied by electromagnetic coupling. The developed network which contains two subnets, a distribution subnet and a scanning subnet, is considered as a first step to design an adaptive microstrip...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jul 2010

    Enhanced IMS Handoff Mechanism for QoS Support Over Heterogeneous Network

    IP Multimedia Subsystem (IMS) is over IP network architecture, but mobile IP cannot directly support session mobility controlled by session initiation protocol-based signaling. The long signaling delay for session reestablishment in application layer always results in session interruptions during the handoff. Therefore, handoff poses a challenge for Quality of Service...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Sep 2010

    Downlink Scheduling and Radio Resource Allocation in Adaptive OFDMA Wireless Communication Systems for User-Individual QoS

    In this paper, the authors address the problem of adaptive Radio Resource Allocation (RRA) and packet scheduling in the downlink of a cellular OFDMA system, and propose a downlink Multi-carrier Proportional Fair (MPF) scheduler and its joint with adaptive RRA algorithm to distribute radio resources among multiple users according to...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Aug 2010

    An Energy-Efficient Virtual MIMO Transmission Scheme for Cluster-Based Wireless Sensor Networks

    In this paper, a cluster-based virtual Multiple-Input Multiple-Output (MIMO) transmission scheme is proposed for energy-constrained wireless sensor networks. Compared with previous work, there are two new aspects in this scheme. Firstly, the proposed scheme makes use of multiple cluster heads cooperative transmission instead of one. Secondly, the Space-Time Block Coding...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Feb 2010

    Investigation of Cooperation Technologies in Heterogeneous Wireless Networks

    Heterogeneous wireless networks based on varieties of Radio Access Technologies (RATs) and standards will coexist in the future. In order to exploit this potential multiaccess gain, it is required that different RATs are managed in a cooperative fashion. This paper proposes two advanced functional architecture supporting the functionalities of interworking...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Dec 2010

    Impact of Deployment Size on the Asymptotic Capacity for Wireless Ad Hoc Networks Under Gaussian Channel Model

    In this paper, the authors studied the impact of the size of the deployment region on the asymptotic unicast and multicast throughput capacity for wireless networks under Gaussian channel model. They derived asymptotic matching upper-bounds and lower-bounds of unicast capacity for arbitrary and random wireless networks in different cases. Their...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Sep 2010

    Energy-Efficient Transmission Schemes in Cooperative Cellular Systems

    Energy-efficient communication is an important requirement for mobile devices, as the battery technology has not kept up with the growing requirements stemming from ubiquitous multimedia applications. This paper considers energy-efficient transmission schemes in cooperative cellular systems with unbalanced traffic between uplink and downlink. Theoretically, the authors derive the optimal transmission...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Feb 2011

    K-Means Based Clustering on Mobile Usage for Social Network Analysis Purpose

    The development of mobile network technology provides a great potential for social networking services. This paper studied data mining for social network analysis purpose, which aims at find people's social network patterns by analyzing the information about their mobile phone usage. In this research, the real database of MIT's Reality...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jun 2010

    Interference Mitigation for Coexistence of Heterogeneous Ultra-Wideband Systems

    Two Ultra-WideBand (UWB) specifications, that is, Direct-Sequence (DS) UWB and MultiBand-Orthogonal Frequency Division Multiplexing (MB-OFDM) UWB, have been proposed as the candidates of the IEEE 802.15.3a, competing for the standard of high-speed Wireless Personal Area Networks (WPAN). Due to the withdrawal of the standardization process, the two heterogeneous UWB technologies...

    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 // 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 // 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

    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 2011

    Supernode Election Algorithm in P2P Network Based Upon District Partition

    Nowadays the idea of Peer-To-Peer (P2P) has been used in many fields, such as file sharing, cooperative processing, information sharing and communication etc. According to the definition, the Peer-To-Peer (P2P) network is a type of Internet network allowing a group of computer users with the same networking program to connect...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Feb 2011

    UWB Channel Estimation Based on Distributed Bayesian Compressive Sensing

    In order to solve the high sampling rate issue in the multiuser UWB communication network system, the authors process the received signal with Bayesian compressive sensing. Using the characteristic that the wireless channels of multiuser signals which are received by one receiver at the same time are statistically related, a...

    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 // 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 // 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 // Jan 2010

    Telecommunication Would Deliver More Managed Services for SMEs: Trends and Prosperity

    Small and Medium Enterprises (SMEs) find running business troublesome not only for improving core competitiveness, but also in the aspect of taking care of IT infrastructure. However, seemingly they cannot get the expected results due to the lack of IT specialists. On the other hand, with the substitution effect of...

    Provided By Beijing University of Posts and Telecommunications

  • White Papers // Jun 2009

    New Birthday Attacks on Some MACs Based on Block Ciphers

    Message Authentication Code (MAC) is a fixed length information used to en-sure data integrity and authenticity, and is widely used in network and security protocols, such as IPSec, SNMP, and SSL/TLS. This paper develops several new techniques of cryptanalyzing MACs based on block ciphers, and is divided into two parts....

    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 // 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