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Fast Implementation of MSSNR TEQ for DMT Systems

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The Journal of China Universities of posts and telecommunications 2003年第4期10卷 65-70页

作者： DING Jia-xin,ZHOU Zheng(school of Telecommunication Engineering, beijing university of posts and telecommunications, beijing 100876, P.R. China) school of Telecommunication Engineering Beijing University of Posts and Telecommunications 北京 100876

The major approaches to the Time-Domain Equalizer (TEQ) design in DMT systemsare summarized. After pointing out that the optimal design method of Maximum ShorteningSignal-to-Noise Ration (MSSNR) TEQ can't be real-time implemented by DSP, we present a suboptimalMSSNR TEQ design method, which reduces the computational complexity greatly by using a new method toestimate the optimal delay Δ and a proposed step-by-step algorithm to compute the TEQ taps. Theresults of simulations show the validity of the suboptimal method.

关键词： discrete multitone modulation time-domain equalizer shortening SNR optimaldelay

A Certain Kind of Non-Degenerate Solvable Lie Algebra on C

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The Journal of China Universities of posts and telecommunications 1998年第2期5卷 60-64页

作者： Mo Jiao (Department of Basic science. beijing university of posts and telecommunications, beijing, 100876, P. R. China)

This paper deals with the non-degenerate solvable Lie algebra. They are divided into the direct sum of root subspaces under certain conditions. Some properties of these subspaces are shown in this paper.

关键词： ideal direct sum root subspace

Analysis and experimentation of key technologies in service-oriented optical internet

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science China(Information sciences) 2011年第2期54卷 215-226页

作者： JI YueFeng, REN DanPing, LI Hui, LIU XueJun & WANG ZhengZhong Key Laboratory of Information Photonics and Optical Communications, Ministry of Education, beijing university of posts and telecommunications, beijing 100876, China 1. Key Laboratory of Information Photonics and Optical Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

To satisfy diverse bandwidth-intensive applications envisioned in the internet of the future, research on a distributed optical internet, enabling efficient utilization of geographically distributed resources, has become attractive. The deployment of such a network, however, has its own technical challenges, including network architecture, resource management, and high-speed transmission. To address these issues, a service-oriented-architecture-based distributed optical internet architecture is proposed. Thereafter, key technologies of an optical internet, such as optical multicasting, distributed resource control, and high-speed transmission, are analyzed and investigated. The proposed schemes are verified through experimentation and simulation.

关键词： optical internet service-oriented distributed optical networks optical multicasting optical transmission

QoS Multicast Routing Based on Ant Algorithm in Internet

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The Journal of China Universities of posts and telecommunications 2000年第4期7卷 12-17页

作者： LU Guo ying, LIU Ze min (school of Telecommunication Engineering, beijing university of posts and telecommunications,beijing 100876,P.R.China) school of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

In this paper, based on ant algorithm, we propose a QoS multicast routing scheme in Internet. We first describe ant algorithm model and give ant network model, then present an approach using ant algorithm to optimize the multicast routes with QoS constaints. Finally, simulations has been made to show the efficiency of the approach in the environment of OPNET simulation software, and the simulation results show that the proposed approach can find the best optimal multicast routes which can satisfy the delay bounded requirement and avoid congested nodes as soon as possible.

关键词： multicast ant algorithm optimization pheromone table internet

Robust Virtual Network Embedding Based on Component Connectivity in Large-Scale Network

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China Communications 2017年第10期14卷 164-179页

作者： Xiaojuan Wang Mei Song Deyu Yuan Xiangru Liu beijing university of posts and telecommunications Beijing 100876 China People's Public Security university of China Beijing China

Virtual network embedding problem which is NP-hard is a key issue for implementing software-defined network which is brought about by network virtualization. Compared with other studies which focus on designing heuristic algorithms to reduce the hardness of the NP-hard problem we propose a robust VNE algorithm based on component connectivity in large-scale network. We distinguish the different components and embed VN requests onto them respectively. And k-core is applied to identify different VN topologies so that the VN request can be embedded onto its corresponding component. On the other hand, load balancing is also considered in this paper. It could avoid blocked or bottlenecked area of substrate network. Simulation experiments show that compared with other algorithms in large-scale network, acceptance ratio, average revenue and robustness can be obviously improved by our algorithm and average cost can be reduced. It also shows the relationship between the component connectivity including giant component and small components and the performance metrics.

关键词： large-scale network component connectivity virtual network embedding SDN

On the bounds of frequency-selective channel capacity with doubly correlated geometrical MIMO channel model

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The Journal of China Universities of posts and telecommunications 2010年第2期17卷 8-13页

作者： LI Yong-hua , Lü Tie-jun, WU Xiao-fei, ZHANG Lin Key Laboratory of Universal Wireless Communications, Ministry of Education, beijing university of posts and telecommunications, beijing 100876, China [a] Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts telecommunications Beijing 100876 China

The multi-input multi-output （MIMO） technology plays an important role in link transmissions. This article considers the general case for the ergodic capacity in doubly correlated frequency-selective MIMO channel. In the study, the geometrical MIMO channel model is presented. Based on the formula of MIMO ergodic capacity, the capacity limits are studied with arbitrary finite number of antennas in the frequency-selective MIMO channel. It first derives the exact expressions for the upper bound and lower bound in doubly correlated MIMO channel. The results for the single-ended correlation and independent identically distributed （i.i.d.） MIMO channel are also obtained as special cases. Then the simple expressions of the capacity bounds are attained at high SNR. Finally, results are provided by Monte Carlo simulations to verify the tightness of the derived bounds.

关键词： MIMO correlation capacity bounds

Spectral efficient half-duplex relaying with interference suppression

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The Journal of China Universities of posts and telecommunications 2010年第6期17卷 19-24页

作者： LI Xing-zheng,LIU Yuan-an,XIE Gang,CHANG Ling-jun,HAN Xiao Key Laboratory of Universal Wireless Communications,Ministry of Education,beijing university of posts and telecommunications,beijing 100876,China [a] Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts telecommunications Beijing 100876 China

Two-hop relaying systems suffer spectral efficiency loss due to the half-duplex property of relays. This paper proposes an efficient relaying protocol which can recover the spectral efficiency loss but still work with half-duplex relays. However,there exists inter-relay interference which degrades the performance of the protocol. With this consideration,a power control policy is derived to suppress the interference using game theory,and then an algorithm is given to facilitate distributed implementation. Furthermore,impact of deploying more destination antennas on performance of the relaying protocol is investigated. Simulation results show that,with the power control policy,the proposed relaying protocol can achieve high spectral efficiency.

关键词： relaying protocol distributed power control cooperative communication decode-and-forward relay game theory

Symbolic Computation Study of (2+1)-Dimensional Dispersive Long Wave Equations

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Communications in Theoretical Physics 2006年第8期46卷 199-202页

作者： LU Zhuo-Sheng~(1,2,+) and XIE Fu-Ding~(2,3) ~1school of science, beijing university of Post and {4., beijing 100876, China ~2Key Laboratory of Mathematics Mechanization, Academy of Mathematics and System sciences, the Chinese Academy of sciences, beijing 100080, China ~3Department of Computer science, Liaoning Normal university, Dalian 116029, China Department of Otolaryngology University Hospital VU P.O. Box 7057 1007 MB Amsterdam The Netherlands school of science Beijing University of Post and Telecommunications Beijing 100876 China

Seeking exact analytical solutions of nonlinear evolution equations is of fundamental importance in mathematical physics. In this paper, based on a constructive algorithm and symbolic computation, abundant new exact solutions of the (2+1)-dimensional dispersive long wave equations are obtained, among which there are soliton-like solutions, mult-soliton-like solutions and formal periodic solutions, etc. Certain special solutions are considered and some interesting localized structures are revealed.

关键词： dispersive long wave equations symbolic computation exact solution localized structure

The Performance Comparisons between the Unconstrained and Constrained Equalization Algorithms

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The Journal of China Universities of posts and telecommunications 2003年第4期10卷 50-58页

作者： HE Zhong-qiu,LI Dao-ben(school of Information Engineering, beijing university of posts and telecommunications, beijing 100876, P. R. China) school of Information Engineering Beijing University of Posts and Telecommunications 北京 100876

This paper proposes two unconstrained algorithms, the Steepest Decent (SD)algorithm and the Conjugate Gradient (CG) algorithm, based on a superexcellent cost function. At thesame time, two constrained algorithms which include the Constrained Steepest Decent (CSD) algorithmand the Constrained Conjugate Gradient algorithm (CCG) are deduced subject to a new constraincondition. They are both implemented in unitary transform domain. The computational complexities ofthe constrained algorithms are compared to those of the unconstrained algorithms. Resultingsimulations show their performance comparisons.

关键词： transform domain adaptive equalization constrained equalization algorithm