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Science china(information Sciences) 2010年第2期53卷 344-354页

作者： LI Bin , ZHOU Zheng & ZOU WeiXia Key Laboratory of Universal Wireless communications, Ministry of Education Wireless Network Laboratory, beijing university of posts and telecommunications, beijing 100876, china 1. Key Laboratory of Universal Wireless communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China2. Wireless Network Laboratory Beijing University of Posts and Telecommunications Beijing 100876 China

With the development of communication technology, the precious frequency spectrum is becoming more and more crowded. Exploiting the particular filter with zero group delay, ultra narrow band (UNB) modulation is intended for acquiring the high frequency efficiency. Unfortunately, this UNB filter is confronted with great challenges from the classical communication theories. The validation on its realization is also difficult. This paper proposes a novel UNB modulation, namely random pulse position keying (RPPK). It is demonstrated from analysis that there is no inessential discrete spectral line in modulated signal’s power density spectrum (PDS), and the UNB filter has been successfully avoided. Consequently, RPPK is rather explicit in theory and simple in implementation. As is shown by the simulation, the frequency utilization of RPPK can even reach 100 bits/s/Hz. Its optimum receiving performance is slightly inferior to BPSK, yet is much superior to that of other UNB modulations such as VMSK/2. Moreover, multi-access and confidentiality are additional benefits to UNB users.

关键词： UNB modulation frequency utilization efficiency RPPK PDS

Novel resource allocation algorithms for multiuser downlink MIMO-OFDMA of FuTURE B3G systems

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Progress in Natural Science:Materials International 2009年第9期19卷 1141-1146页

作者： Qiaoyun Sun, Hui Tian *, Shuang Wang, Kun Dong, Ping Zhang Key Laboratory of Universal Wireless communication, Ministry of Education, Wireless Technology Innovation Institute, beijing university of posts & telecommunications, beijing 100876, china [a]Key Laboratory of Universal Wireless communication Ministry of Education Wireless Technology Innovation Institute Beijing University of Posts & Telecommunications Beijing 100876 China

In this paper, subcarrier and power allocation problems for multiuser downlink MIMO-OFDMA of the FuTURE B3G TDD system are investigated. For the reciprocity of the TDD channel, the channel state information can be employed at the transmitter, thus eigen beamforming can be implemented efficiently. With the goal of minimizing the total transmit power under the condition that the QoS requirement of each user can be guaranteed, a novel dynamic resource allocation scheme is proposed to exploit the multiuser diversity gain. The proposed algorithm involves adaptive subcarrier allocation, adaptive modulation and eigen beamforming and achieves significant improvement in overall system performance. Based on the proposed scheme, a modified bit and power allocation is developed. The modified scheme reduces the computational complexity at little expense of system performance. Numerical simulations show that the proposed algorithm and the modified scheme can decrease the total transmit power effectively.

关键词： Adaptive modulation and coding Dynamic resource allocation Eigen beamforming MIMO–OFDMA

On Personal communication

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The Journal of china Universities of posts and telecommunications 1995年第1期2卷 50-54页

作者： Zhou Jiongpan(Department of information engineering, beijing university of posts and telecommunications beijing 100088, P.R. china) Department of information engineering Beijing University of Posts and Telecommunications Beijing 100088 P. R. China

This paper first gives a definition for personal communication, then discusses some key problems to besolved in realizing PC and lastly gives some personal suggestions.

关键词： personal communication multi-access,satellite communication

communication Software Reuse and Its Supporting Environment

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The Journal of china Universities of posts and telecommunications 1998年第1期5卷 76-77页

作者： Zhou Chen directed by Chen Junliang (Department of information engineering, beijing university of posts and telecommunications, beijing 100876, P. R. china)

Summary of Software Reuse What we mean 'software reuse' is that we use those software components that were developed before in the new environment. Increasing the productivity and reliability of software is an important task in the development of software. One of the most promising techniques for achieving a significant level of improvement is reuse. The reuse process occurs in every phase of software life cycle: analysis, design, coding, testing, and maintenance. The technologies applied to the reusability can be divided into two major groups depending on the nature of the components being reused. These two major groups are composition approach and generation approach. Both of the approaches have their advantages and drawbacks and there is no agreement upon a unique approach to reusability. We choose composition approach. In this paper, we focus on the research of switching software reuse. There has been no report on the research of communication software reuse in china. The research was carried out in Japan and U.S.A. in the middle of 1980′s. Some references report that there are many advantages in using object oriented language C++ in the development of 5ESS switching system. The software reusability is high and the productivity is also greatly improved. It seems that every switching system has its own software supporting tools or environment. The aim is the same and the reusing technologies are somewhat different. Three main reuse methods are listed below: (1) Paradigm method; (2) Knowledge Base method; (3) Object oriented method. 2 Main Researches (1) Research on the integrated environment for SDL (IES). (2) Convert Abstract Data Types(ADT) in SDL specification to CHILL implementation; By using IF_THEN_ELSE rewriting rules, we prove the correctness of conversion. (3) Introduce the concept of reuse into SDL, and design and implement a SDL ADT/CHILL reusable component library. We focus on the Di

关键词： SDL specification software reuse object orientation

Performance Analysis of Interconnected communication Networks

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The Journal of china Universities of posts and telecommunications 1998年第1期5卷 72-72,75页

作者： Wang Jianli directed by Zhou Jiongpan (Department of information engineering, beijing university of posts and telecommunications, beijing 100876, P. R. china)

As the means for communication of users in different communication networks and network resource sharing, communication network interconnection has been paid great attention to in recent years. The performance analysis of internetworks is very important in communication network interconnection, for it is the basis for the study of other problems concerned. The main contribution of this paper is a wide and deep study of performance of internetwork, the construction of systematic performance analysis method for arbitrary internetworks, and of queuing model for gateways. In this paper, the performance analysis of internetwork with arbitrary topology is studied for the first time, and a new method - Node Equivalence of Subnetworks (NES) is proposed. The key step of this method is the node equivalence of subnetworks of all kinds, so we first deeply study the node equivalence, and develop two models for node equivalence. Then we study the node equivalence of CSMA/CD and SLOTTED ALOHA systems by using these models. The results show that the NES method is a systematic method which is suitable for performance analysis of any type of internetworks. The proposed equivalence models is usable with good approximation. The queuing model of gateway is first widely studied in this paper. The queuing model for gateways with packet fragmentation and reassembly is studied for the first time and the analysis method, proposed. In the analysis, two modeling tools, Reversed Switched Poisson Process (RSPP) and Switched Determined Process (SDP), are proposed and RSPP/M/1 queue and SDP/D/1 queue, analyzed. A new method-minislot method is proposed and used for the study of SDP/D/1 queue and performance of ATM multiplexer. In this paper, the interdeparture time distribution of ATM network under some input traffic models is studied and the expression, derived. These results can be used for both performance evaluation of ATM network and the performance of ATM networks intercon

关键词： interconnected communication network internetworks gateway subnetworks node equivalence

Digital Rights Management：Model,Technology and Application

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china communications 2017年第6期14卷 156-167页

作者： Zhaofeng Ma school of Cyberspace Security Beijing University of Posts and Telecommunications Beijing 100876 China

with rapid achievement of current information technology and computing ability and applications,much more digital content such as films,cartoons,design drawings,office documents and software source codes are produced in daily work,however to protect the content being copying,shared or deliberately stolen by inside or outside,digital rights management(DRM) became more and more important for digital content *** this paper,we studied various DRM model,technology and application,and first proposed DRM Security Infrastructure(DSI),in which we defined encryption,hash,signature algorithm,watermarking algorithms,authentication,usage control,trusted counter,conditional trace,secure payment,and based on the DSI we then proposed a whole classification approach and architecture of all kinds of DRMs,in which we proposed 6 typical classes of copyrights and content protection DRMs architecture:(1) Software-oriented DRM,(2) e Book-oriented DRM,(3) Video-oriented DRM,(4) Image-Oriented DRM(5) Unstructured data oriented DRM,(6) Text-oriented *** on the above DSI,we then proposed a dynamic DRM model selection method for various DRM application,which can be adapted dynamically for different technology of different applications,which can provide awhole solution for variant DRM development in a rapid and customized *** proposed DRM method,technology and application in this paper provided a common,flexible and extendable solution for variant DRM scenes,and can support rapid and customized ***,we proposed an opinion that the future life will enter into a new era that the content usage and consumption will not again adopt DRM technology rather than with law,liberty and morality.

关键词： digital rights management drm security infrastructure encryption watermark usage control drm-free

Threshold quantum secret sharing between multi-party and multi-party

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Science china(Physics,Mechanics & Astronomy) 2008年第9期51卷 1308-1315页

作者： YANG YuGuang1,2,3 & WEN QiaoYan4 1 College of Computer Science and Technology,beijing university of Technology,beijing 100124,china 2 State Key Laboratory of Integrated Services Network,Xidian university,Xi’an 710071,china 3 State Key Laboratory of information Security (Graduate university of Chinese Academy of Sciences),beijing 100049,china 4 State Key Laboratory of Networking and Switching Technology,beijing university of posts and Tele-communications,beijing 100876,china College of Computer Science and Technology Beijing University of Technology Beijing 100124 China State Key Laboratory of Integrated Services Network Xidian University Xi’an 710071 China State Key Laboratory of information Security (Graduate university of Chinese Academy of Sciences) Beijing 100049 China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

A threshold quantum secret sharing (TQSS) scheme between multi-party and multi-party was proposed using a sequence of single photons,which is useful and efficient when the parties of communication are not all present. We described the process of this TQSS scheme and discussed its security. It was shown that entan-glement is not necessary for quantum secret sharing. Moreover,the theoretic effi-ciency was improved to approach 100% as almost all the instances can be used for generating the private key,and each photon can carry one bit of information. This protocol is feasible with the present-day technique.

关键词： threshold quantum secret sharing quantum cryptography single photon multi-party and multi-party

OpenMP compiler for distributed memory architectures

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Science china(information Sciences) 2010年第5期53卷 932-944页

作者： WANG Jue , HU ChangJun, ZHANG JiLin & LI JianJiang school of information and engineering, university of Science and Technology beijing, beijing 100083, china 1. school of information and engineering University of Science and Technology Beijing Beijing 100083 China

OpenMP is an emerging industry standard for shared memory architectures. While OpenMP has advantages on its ease of use and incremental programming, message passing is today still the most widely-used programming model for distributed memory architectures. How to effectively extend OpenMP to distributed memory architectures has been a hot spot. This paper proposes an OpenMP system, called KLCoMP, for distributed memory architectures. Based on the "partially replicating shared arrays" memory model, we propose an algorithm for shared array recognition based on the inter-procedural analysis, optimization technique based on the producer/consumer relationship, and communication generation technique for nonlinear references. We evaluate the performance on nine benchmarks which cover computational fluid dynamics, integer sorting, molecular dynamics, earthquake simulation, and computational chemistry. The average scalability achieved by KLCoMP version is close to that achieved by MPI version. We compare the performance of our translated programs with that of versions generated for Omni+SCASH, LLCoMP, and OpenMP(Purdue), and find that parallel applications (especially, irregular applications) translated by KLCoMP can achieve more effective performance than other versions.

关键词： parallel compiling high performance computing distributed memory architecture OpenMP irregular application

A New Image Process CNN

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A New Image Process CNN