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Novel THP algorithms with minimum BER criterion for MIMO broadcast communications

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The Journal of china Universities of posts and {3. 2009年第4期16卷 71-77页

作者： YUN Xiang,L tie-jun School of information and communication {3.,beijing university of posts and telecommunications,beijing 100876,china [a]School of information and communication engineering beijing university of posts and telecommunications beijing 100876 china

In this article, two novel Tomlinson-Harashima precoding （THP） algorithms are proposed at the downlink broadcast channel of multi-user multiple-input multiple-output （MIMO） systems. The optimality criterion is the minimization of the bit error rate （BER） at the receiver with a constraint on the overall transmitted power. In these algorithms, transmit power allocation （TPA） matrix is introduced to the traditional THP algorithms as part of the precoding matrix. This leads to a power loading operation based on substreams signal to interference-plus-noise ratio （SINR） and results in improvement of the error rate performance compared with traditional THP algorithms. When the precoding loss factor is considered, further performance improvement is achieved by the enhanced algorithm.

关键词： MIMO system THP minimum bit-error rate (MBER) broadcast communication

Transmit-reference UWB system based on m-sequence codes

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The Journal of china Universities of posts and {3. 2010年第1期17卷 25-31页

作者： ZHAO Lin-li,Lü tie-jun,QIAO Yong-wei School of information and {3. engineering,beijing university of posts and telecommunications,beijing 100876,china [a] School of information communication engineering Beijing University of Posts telecommunications Beijing 100876 China

In this article, a novel transmit-reference （TR） signaling scheme is proposed for ultra-wideband （UWB） system, where by invoking m-sequence codes the reference and data pulses can be transmitted side by side to increase the data rate. This structure enables demodulation with a simple and practical autocorrelation receiver despite existence of severe inter-pulse interference （IPI） To evaluate detection performance of the new designs, closed-form expression for bit error probability （BRP） is theoretically derived and simulation results confirm the analytical results. In addition, the proposed scheme can be extended to M-ary systems to further improve the data rate and power efficiency.

关键词： UWB TR IPI m-sequence M-ary

Radio resource management strategy for VoIP service in TD-HSDPA system

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The Journal of china Universities of posts and {3. 2009年第4期16卷 29-33页

作者： HE Da-jiang ,CUI Jie,CHANG Yong-yu,YANG Da-cheng School of communication and information {3.,beijing university of posts and telecommunications,beijing 100876,china [a]School of communication and information engineering beijing university of posts and telecommunications beijing 100876 china

In this article, the performance of a novel radio resource management （RRM） strategy for voice over IP （VoIP） service will be evaluated in low code rate （LCR） time duplex high speed downlink packet access （TD-HSDPA） system. This novel RRM strategy is studied from the aspects of scheduling algorithm and time slot assignment algorithm. As VolP is delay sensitive service, the delay based proportional fair （DBPF） scheduler is proposed in this article. Smart antenna （SA）, which is adopted in LCR TD-HSDPA, can obtain spatial information from the direction of arrival （DOA） estimation. To exploit this spatial information further, a dynamic time slot allocation （DTA） algorithm is introduced to cooperate with the DBPF scheduler. The performance of the round robin （RR）, proportional fair （PF） with the random time slot allocation （RTA） algorithm will be given to demonstrate the benefits of this novel DBPF with DTA RRM strategy. The system level simulation results prove that the performance of this novel RRM strategy is the best of all the RRM strategies.

关键词： RRM smart antenna VolP DBPF DTA HARQ AMC

Performance analysis of rate-adaptive cooperative MAC based on wireless local area networks

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The Journal of china Universities of posts and {3. 2009年第5期16卷 78-85页

作者： ZHANG Yang , XU Hong-kun, CHANG Yong-yu, YANG Da-cheng, WANG Ya-feng School of information and communication {3., beijing university of posts and telecommunications, beijing 100876, china [a]School of information and communication engineering beijing university of posts and telecommunications beijing 100876 china

Bi-dimensional Markov chain model based on cooperative medium access control （MAC） of wireless local area networks （WLAN） is considered to reflect system performance accurately. Two basic factors that affect the analysis results are station retry limits and non-saturated transmit probability. A uniform solution considering both factors is proposed. To prove the theoretical analysis, a cooperative MAC （CoopMAC） topology is established and the simulation model is enhanced by changing the cooperative table to the nodes＇ memory with more information added. Meanwhile, the three-way handshake scheme is modified and a handshake threshold is set based on the packet size. Simulation results show the performance analytical model is accurate, and the rate-adaptive cooperative MAC protocol significantly improves the network performance in terms of non-saturated system throughput and delay.

关键词： performance analysis cooperative MAC bi-dimensional Markov Chain non-saturated transmit station retry limit

Home Network and Digital Rights Management Technology

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ZTE communications 2006年第4期4卷 12-18页

作者： Yang cheng 1Wang Yongbin 2Yang Yixian 3.1. information engineering School, {3. university of china, beijing 100024, china 2. Computer and Software School, {3. university of china, beijing 100024, china 3. information Security Center, beijing university of posts and telecommunications, beijing 100876, china) china china china

The home network is a major concern for the growth of digital and information society. Yet, how to guarantee the security of its digital content and protect the legal benefits for each section of the value chain becomes a crucial "bottleneck" in the home network development. The Digital Rights Management (DRM) technology provides total solution for usage, storage, transfer, and tracing the digital contents and rights. Its basic features are systematic and controllability. Considering the growth of the new media and services and the requirements of the Intellectual Property Rights (IPR) protection in a home network, it's necessary to solve consistency problems in usage, storage, and transfer of contents and rights. In addition, it is inevitable to conduct researches of key techniques such as end-to-end secure transmission, conditional access and play, and right description.

关键词： HDCP Home Network and Digital Rights Management Technology ZTE ISDB ATSC

Secure Beamforming Design for SWIPT in Cooperative D2D communications

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china communications 2017年第1期14卷 20-33页

作者： Li Jiang cheng Qin Xixi Zhang Hui Tian State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunicationsand Science and Technology on Information Transmission and Dissemination in Communication Networks LaboratoryBeijing100876China

In device-to-device(D2D) communications, device terminal relaying makes it possible for devices in a network to function as transmission relays for each other to enhance the spectral efficiency. In this paper we consider a cooperative D2D communication system with simultaneous wireless information and power transfer(SWIPT). The cooperative D2D communication scheme allows two nearby devices to communicate with each other in the licensed cellular bandwidth by assigning D2D transmitters as half-duplex(HD) relay to assists cellular downlink transmissions. In particular, we focus on secure information transmission for the cellular users when the idle D2D users are the potential eavesdroppers. We aim to design secure beamforming schemes to maximize the D2D users data rate while guaranteeing the secrecy rate requirements of the cellular users and the minimum required amounts of power transferred to the idle D2D users. To solve this non-convex problem, a semi-definite programming relaxation(SDR) approach is adopted to obtain the optimal solution. Furthermore, we propose two suboptimal secure beamforming schemes with low computational complexity for providing secure communication and efficient energy transfer. Simulation results demonstrate the superiority of our proposed scheme.

关键词： device-to-device(D2D) communications half-duplex relaying physical layer security secure beamforming simultaneous wireless information and power transfer

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密码学原语中信任传递语义研究

通信学报 2008年第12期29卷 60-65页

作者：王励成潘耘谷利泽杨义先北京邮电大学网络与交换技术国家重点实验室信息安全中心中国传媒大学计算机学院

以可信计算和信任管理为背景,考察密码学原语中所包含的信任传递语义,进而借助于目前较为成熟的密码学理论为信任传递机理进行建模,提出了信任传递语义模型的雏形,分析了多种典型数字签名原语中的信任传递语义。分析结果表明所提模型具... 详细信息

以可信计算和信任管理为背景,考察密码学原语中所包含的信任传递语义,进而借助于目前较为成熟的密码学理论为信任传递机理进行建模,提出了信任传递语义模型的雏形,分析了多种典型数字签名原语中的信任传递语义。分析结果表明所提模型具有很强的概括能力。最后,展望了该模型在IP网络信任管理系统设计及分析中的潜在应用。

关键词：密码学原语信任传递语义

THE RELATIONSHIPS AMONG DATA SYMBOLS SATISFIED FOR SIDELOBE SUPPRESSION IN MB-OFDM COGNITIVE RADIOS

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THE RELATIONSHIPS AMONG DATA SYMBOLS SATISFIED FOR SIDELOBE ...

An Audio Zero-Watermark Scheme Based on Energy Comparing

2009 IEEE International Conference on communication Technology and Applications（ICCTA2009）

作者： Zhigang Xu cheng Yang weixia Zou zheng Zhou Key Lab of Universal Wireless {3.s MOE Wireless Network Lab beijing university of posts and telecommunications beijing 100876 china

＜正＞From the mathematic expression,we can see that sidelobe power of multi-band orthogonal frequency-division multiplexing（MB-OFDM） signal is a function of the data symbols loaded on the *** the derivation of the minimum of the function,relationships among data symbols, which help to suppress sidelobes,are *** types of methods,referred as Sub-carrier Adding（SA） method and Sub-carrier Multiplying（SM） method, are proposed,which realize the relationships at the cost of small degradation in information transmission *** a result,with the proposed methods,the sidelobe power can be *** results also prove this.

关键词： OFDM sidelobe suppression data symbols relationships

来源： cnki会议评论

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china communications 2014年第7期11卷 110-116页

作者： YANG Yu LEI Min cheng Mingzhi LIU Bohuai LIN Guoyuan XIAO Da information Security Center Beijing University of Posts and Telecommunications Beijing China College of information engineering Beijing Institute of Graphic Communication Beijing China National engineering Laboratory for Disaster Backup and Recovery Beijing China School of Computer Science and Technology China University of Mining and Technology China

Zero-watermark technique,embedding watermark without modifying carriers,has been broadly applied for copyright protection of ***,there is little research on audio *** paper proposes an audio zero-watermark scheme based on energy relationship between adjacent audio *** use of discrete wavelet transformation(DWT),it gets power approximations,or energies,of audio ***,it extracts the audio profile,*** zero-watermark,according to the relative size of energies of consecutive *** experimental results demonstrate that the proposed scheme is robust against general malicious attacks including noise addition,resampling,low-pass filtering,etc.,and this approach effectively solves the contradiction between inaudibility and robustness.

关键词： zero-watermark audio water-marking scheme energy comparing