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Location based spectrum sensing performance analysis over fading channels in cognitive radio networks

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The Journal of China Universities of posts and telecommunications 2010年第5期17卷 26-31页

作者： YAO Hai-peng,ZHOU Zheng,SUN Xuan,LI Bin School of Information and Communication Engineering,Beijing university of posts and telecommunications,Beijing 100876,China [a] School of Information Communication Engineering Beijing University of Posts telecommunications Beijing 100876 China

This paper analyzes the spectrum sensing performance over fading channel,in which a licensee and multiple unlicensed users coexist and operate in the licensed channel in a local *** overall average probabilities of detection and false alarm by jointly taking the fading and the locations of all secondary users into account are derived,and a statistical model of cumulate interference is *** on the cumulate interference,a closed-form expression of outage probability at the primary user’s receiver according to a specific distribution of the fading is ***,the sensing parameters so as to minimize the total spectrum sensing error and maximize the average opportunistic throughput are *** is noted that the overall average performance analysis and results here enable to benchmark the design of specific spectrum sensing algorithms.

关键词： spectrum sensing cognitive radio cumulate interference outage probability

Improved discriminative training for generative model

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The Journal of China Universities of posts and telecommunications 2009年第3期16卷 126-130页

作者： WU Ya-hui,GUO Jun,LIU Gang Laboratory of Pattern Recognition and Intelligent System,Beijing university of posts and telecommunications,Beijing 100876,China [a]Laboratory of Pattern Recognition and Intelligent System Beijing university of posts and telecommunications Beijing 100876 China

This article proposes a model combination method to enhance the discriminability of the generative model. Generative and discriminative models have different optimization objectives and have their own advantages and drawbacks. The method proposed in this article intends to strike a balance between the two models mentioned above. It extracts the discriminative parameter from the generative model and generates a new model based on a multi-model combination. The weight for combining is determined by the ratio of the inter-variance to the intra-variance of the classes. The higher the ratio is, the greater the weight is, and the more discriminative the model will be. Experiments on speech recognition demonstrate that the performance of the new model outperforms the model trained with the traditional generative method.

关键词： model combination discriminability generative model training speech recognition

Robust multiuser MIMO scheduling algorithms with imperfect CSI

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Science China(Information Sciences) 2012年第4期55卷 815-826页

作者： MAO JunLing 1,3,GAO JinChun 1,3,LIU YuanAn 1,3,XIE Gang 2,3 & ZHANG Jian 1,3 1 School of Electronic Engineering,Beijing university of posts and telecommunications,Beijing 100876,China 2 School of Information and Communication Engineering,Beijing university of posts and telecommunications,Beijing 100876,China 3 Key Lab of Universal Wireless Communications,Ministry of Education,Beijing university of posts and telecommunications,Beijing 100876,China 1. School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China3. Key Lab of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China2. School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Robust multiuser multiple-input-multiple-output (MIMO) scheduling algorithms are proposed in this *** imperfect channel state information (CSI),traditional scheduling algorithms for the multiuser MIMO system based on the zero forcing precoding scheme will lose some performance due to the multi-user interference (MUI).In order to improve the system average throughput,we study the robust multiuser MIMO scheduling problem with imperfect *** the average capacity formula,we derive a robust factor which can transform the robust multiuser MIMO scheduling problem into the traditional one,thus most existing non-robust scheduling algorithms can be robust if this factor is *** results show that compared with the traditional algorithms,the proposed robust algorithms can improve the system average throughput significantly under the CSI error environment.

关键词： multiuser MIMO (MU-MIMO) scheduling robust imperfect CSI

An Exact Virtual Network Embedding Algorithm Based on Integer Linear Programming for Virtual Network Request with Location Constraint

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China Communications 2016年第8期13卷 177-183页

作者： Zeheng Yang Yongan Guo School of Computer Science and Engineering University of Electronic Science and Technology of China(UESTC) College of telecommunications and Information Engineering Nanjing University of Posts and Telecommunications

Network virtualization is known as a promising technology to tackle the ossification of current Internet and will play an important role in the future network area. Virtual network embedding(VNE) is a key issue in network virtualization. VNE is NP-hard and former VNE algorithms are mostly heuristic in the *** exact algorithms have been developed in recent years. However, the constraints of exact VNE are only node capacity and link *** on these, this paper presents an exact VNE algorithm, ILP-LC, which is based on Integer Linear Programming(ILP), for embedding virtual network request with location constraints. This novel algorithm is aiming at mapping virtual network request(VNR) successfully as many as possible and consuming less substrate *** topology of each VNR is randomly generated by Waxman model. Simulation results show that the proposed ILP-LC algorithm outperforms the typical heuristic algorithms in terms of the VNR acceptance ratio, at least 15%.

关键词： network virtualization virtual network embedding exact VNE algorithm integer linear Programming location constraint VNR acceptance ratio

Network parameters awareness for routing discovery in autonomic optical Internet

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The Journal of China Universities of posts and telecommunications 2009年第2期16卷 84-88,128页

作者： JIN Jin WANG Hong-xiang JI Yue-feng Key Laboratory of Optical Communication and Lightwave Technologies,Beijing university of posts and telecommunications,Beijing 100876,China [a]Key Laboratory of Optical Communication and Lightwave Technologies Beijing university of posts and telecommunications Beijing 100876 China

The article proposes a network parameter-awareness （NPA） method and applies it to routing discovery algorithms in autonomic optical Internet. This NPA method can perceive the main parameters of the network, such as delay, jitter and traffic, which can represent the current situation of the network. And these parameters enable network to determine the appropriate nodes for routing discovery. The simulation results of evaluating performance of a network with NPA method and its routing applications show that the method and its applications in routing improve the performance of the network significantly with quality of service （QoS） guaranteed.

关键词： NPA autonomic optical Internet self-aware muting QoS

Hopping control channel MAC protocol for opportunistic spectrum access networks

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The Journal of China Universities of posts and telecommunications 2010年第6期17卷 65-71页

作者： FU Jing-tuan,JI Hong,MAO Xu 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

Opportunistic spectrum access （OSA） is considered as a promising approach to mitigate spectrum scarcity by allowing unlicensed users to exploit spectrum opportunities in licensed frequency bands. Derived from the existing channel-hopping multiple access （CHMA） protocol,we introduce a hopping control channel medium access control （MAC） protocol in the context of OSA networks. In our proposed protocol,all nodes in the network follow a common channel-hopping sequence; every frequency channel can be used as control channel and data channel. Considering primary users＇ occupancy of the channel,we use a primary user （PU） detection model to calculate the channel availability for unlicensed users＇ access. Then,a discrete Markov chain analytical model is applied to describe the channel states and deduce the system throughput. Through simulation,we present numerical results to demonstrate the throughput performance of our protocol and thus validate our work.

关键词： channel hopping MAC protocol OSA Markov chain

On the construction of multi-output Boolean functions with optimal algebraic immunity

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Science China(Information Sciences) 2012年第7期55卷 1617-1623页

作者： ZHANG Jie 1,2 ,SONG ShouChao 1 ,DU Jiao 2,3 & WEN QiaoYan 2 1 School of Science,Beijing university of posts and telecommunications,Beijing 100876,China 2 State Key Laboratory of Networking and Switching Technology,Beijing university of posts and telecommunications,Beijing 100876,China 3 Department of Mathematics,Xinxiang university,Xinxiang 453003,China 1. School of Science Beijing University of Posts and Telecommunications Beijing 100876 China2. State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China3. Department of Mathematics Xinxiang University Xinxiang 453003 China

In this paper,we show a construction of multi-output Boolean functions with optimal algebraic ***,the relationship between the algebraic immunity of a multi-output Boolean function and those of its component functions is *** show that all the component functions,together with their nonzero linear combination,of the multi-output Boolean functions achieved by this construction have optimal algebraic immunity simultaneously.

关键词： algebraic immunity Boolean functions algebraic attacks annihilators

Present Status and Future Development of Mobile Internet

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China Communications 2009年第1期6卷 113-118页

作者： Wang Jian1, Bi Houjie2 1Nanjing university, Nanjing 210093, China 2Nanjing university of posts and telecommunications, Nanjing 210003, China Nanjing university Nanjing 210093 China Nanjing university of posts and telecommunications Nanjing 210003 China

With the integration of telecommunications network and Internet, mobile Internet is bound to rise. Mobile Internet brings not only high-quality business experience; but also enormous challenges to telecommunications. The current status and hierarchical structure of the mobile Internet are presented. Technological advances and market demand are promoting development of mobile Internet, and terminals, networks and businesses are three elements of the development of the mobile Internet. Mobile IP technique and related protocols are described systematically, which are designed to allow mobile terminal and the mobile sub-network to roam within the Internet. Then the IP Multimedia Subsystem (IMS) and its architectural framework are expounded, which are designed by (3GPP). The credible and reliable IP network architecture with Quality of Service (QoS) based on IMS is discussed to meet the needs of the next generation of mobile Internet. Finally, the hotspots such as P2P/ Multicast/ Security are pointed out within the mobile Internet.

关键词： Mobile Internet mobile IP IMS network convergence

DESIGN CONSIDERATION OF ERBIUM DOPED FIBER FOR EFFICIENT L-BAND EDFAs

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光子学报 2000年第12期29卷 1138-1140页

作者： Luo Jie,Ye Peida School of Telecommunication Engineering,Beijing university of posts and telecommunications, Beijing 100876,P.R.China Wu Shujian,Chen Shuling Wuhan Research Institute of posts and telecommunications,Wuhan 430074,P.R.China School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China Wuhan Research Institute of posts and telecommunications Wuhan 430074 China

In this paper,the relation between gain coefficient of long wavelength band(L band)EDFA and the Er 3+ ion concentration of erbium doped fiber (EDF) is *** high concentration EDF co doped with aluminium has been developed to shorten the fiber length necessary for L band amplification.L band amplification has been realized with a dual stage pumping *** the total EDF length of 18m,the small signal gain is 42.26dB and the output power is 17.5dBm at *** low concentration quenching effect is believed to be due to the high aluminium concentration in author ***-3dBm total input signal power,the gain tilt of 7 WDM channels from 1570 to 1600nm is only 0.68dB.

关键词： Erbium doped fiber L band EDFA Concentration quenching Gain flatness