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Rate allocation strategies for energy-efficient multipath routing in Ad-hoc networks towards b3g

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 84-88页

作者： ZHAN Song-tao XU guo-xin Wireless Technologies Innovation Institute Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Wireless mobile Ad-hoc network is a special network that all nodes can serf-organize and work together. It is flexible to form a network and extend the coverage area dynamically without infrastructure, so Ad-hoc network is envisioned as cornerstones of future generation networking technologies （b3g or 4（3）. However, the dynamic network topology makes the communication cost not only the energy of source/destination nodes, but also the relay nodes. Another problem of the Ad-hoc network is it is hard to provide a stable and persistent quality of service （QoS）, which is strongly required by the beyond 3rd generation （b3g） system. In this article, the authors establish a scenario that contains b3g cellular base station and Ad-hoc mobile nodes, and propose two algorithms minimum incremental rate algorithm and power feed-back rate allocation algorithm in multipath routing. The algorithms can maintain a constant total transmission rate and bit error ratio （bER） to provide the QoS guarantee and reach the minimum power consumption of the relay nodes by adjusting the rate of each path in the multipath routing.

关键词： Ad-hoc network b3g multipath routing energy consumption QoS

A novel TOA estimation method with effective NLOS error reduction

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 32-37页

作者： ZHANg Yi-heng CUI Qi-mei LI Yu-xiang ZHANg Ping Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications Ministry of Education Wireless Technology Innovation Institute (WTI) Beijing 100876 China

It is well known that non-line-of-sight （NLOS） error has been the major factor impeding the enhancement of accuracy for time of arrival （TOA） estimation and wireless positioning. This article proposes a novel method of TOA estimation effectively reducing the NLOS error by 60%, comparing with the traditional timing and synchronization method. by constructing the orthogonal training sequences, this method converts the traditional TOA estimation to the detection of the first arrival path （FAP） in the NLOS multipath environment, and then estimates the TOA by the round-trip transmission （RTT） technology. both theoretical analysis and numerical simulations prove that the method proposed in this article achieves better performance than the traditional methods.

关键词： TOA estimation NLOS error b3g

The Research on Handoff Strategy in beyond 3g Wireless Networks

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The Journal of China Universities of Posts and Telecommunications 2006年第2期13卷 26-30页

作者： CUI Hong-yan TIAN Hui XU Hai-bo ZHANg Ping College of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

One of the major challenges for beyond third generation mobile .systems is efficient mobility management. This paper proposes a distributed dynamic management .scheme of handoff based on b3g networks. This scheme can reduce the cost of update signalling and transmitting packets, and improve the system capability. In this scheme, the dynamic building network approach is adopted to deduce the update signalling cost. We implement the distributed dynamic management scheme of handoff in a simulation platform and compare its performance with that of general centralized handoff management schemes. Our simulation results indicate that our scheme is capable of reducing the update handoff latency, and enhancing the performance.

关键词： b3g IPv6 handoff AP CA

Competitive Analysis of Different Wireless Technologies

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China Communications 2007年第2期4卷 58-63页

作者： Xi Jiarong Shu Huaying bi Chunli beijing Univ Posts & Telecommun Beijing Peoples R China

This paper takes a closer look at different wireless technologies:WiFi,WiMAX,E3g and b3g,and compares their market potentials,potential applications and areas of competitive threat,co-existence,and potential convergence in future wireless communication markets, so as to provide some available information for the industry in China.Meanwhile,some characteristics of future mobile service are also demonstrated.Moreover,some valuable analysis and suggestions are also proposed for Chinese choice and development of different wireless technologies.

关键词： WiFi WiMAX E3g b3g service

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WLAN与b3g结合的结构框架和接入技术

铁道学报 2006年第4期28卷 60-64页

作者：刘琪李承恕北京交通大学现代通信研究所北京100044

讨论了无线局域网(WLAN)与b3g移动蜂窝网络相结合的意义与发展前景,提出WLAN和b3g网络互连的基本结构框架模型,并对模型的重要组成部分进行分析。该模型采用松耦合的工作方式,结构框架中的WLAN接入网为用户与b3g核心网的业务连接提供了... 详细信息

讨论了无线局域网(WLAN)与b3g移动蜂窝网络相结合的意义与发展前景,提出WLAN和b3g网络互连的基本结构框架模型,并对模型的重要组成部分进行分析。该模型采用松耦合的工作方式,结构框架中的WLAN接入网为用户与b3g核心网的业务连接提供了桥梁,起到了关键性作用。同时在b3g核心网络中加入了无线接入网关(WAg)和数据包网关(PDg),用来为从WLAN接入的用户提供服务。还讨论了两种不同类型用户的移动终端(MT)的接入问题,包括拥有(U)SIM卡的3g注册用户和非3g注册用户。设计出3g注册用户通过WLAN接入b3g网络的流程图和主要程序;同时也提供了非3g注册用户接入b3g核心网络的解决办法和详细进程。

关键词：无线局域网第3代移动蜂窝网 b3g AAA机制

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复合可重构无线移动通信系统分析

铁道学报 2008年第4期30卷 44-49页

作者：李常茗李承恕吴韶波北京交通大学现代通信研究所北京100044

复合可重构无线通信系统是一种向着未来无线通信系统演进的多制式异构无线通信网络解决方案。目前世界范围内的各种研究基本上都是关注两种异构网络的互联互通,关于多制式的异构网络讨论得很少。本文从复合可重构通信系统最基本的结构入... 详细信息

复合可重构无线通信系统是一种向着未来无线通信系统演进的多制式异构无线通信网络解决方案。目前世界范围内的各种研究基本上都是关注两种异构网络的互联互通,关于多制式的异构网络讨论得很少。本文从复合可重构通信系统最基本的结构入手,选取3种具有代表性的接入技术,设定网络环境,将复合可重构通信系统建模成为一个M/H3/m/m排队系统。通过理论分析得到复合通信系统的平均系统信道占用时间、阻塞概率等参数。本文最后部分,通过数值仿真得到复合系统容量和到达率的关系,利用求出的用户容量,将复合可重构无线通信系统与现有的单一无线接入技术构成的系统相比,得出复合可重构通信系统能提供更大的系统容量、能适应更复杂的应用环境的结论。

关键词： 4g b3g 复合异构网络 M/H3/m/m WCDMA IEEE802.11g IEEE802.16e

3g/WLAN网络中基于终端移动与业务认知的动态负载均衡机制

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计算机学报 2010年第9期33卷 1569-1579页

作者：刘琪袁坚山秀明苏伟张宏科清华大学电子工程系北京100084 北京交通大学电子信息工程学院北京100044

下一代无线移动通信要求异构网络之间相互协作,3g蜂窝网与WLAN之间的密切合作将为用户提供无缝的业务链接与多样化通信服务.终端移动与业务时空分布的不均衡性是影响网络性能的重要因素,3g/WLAN网络中业务负载均衡策略是提高网络整体性... 详细信息

下一代无线移动通信要求异构网络之间相互协作,3g蜂窝网与WLAN之间的密切合作将为用户提供无缝的业务链接与多样化通信服务.终端移动与业务时空分布的不均衡性是影响网络性能的重要因素,3g/WLAN网络中业务负载均衡策略是提高网络整体性能的有效途径.首先,文中提出了一种新的基于终端移动与业务认知的动态负载均衡(DLb-MSA)机制,该机制重点关注业务潜在用户,通过动态优化的联合业务接入控制,使得每个无线接入点的业务量与其通信资源保持匹配关系,实现网络的负载均衡.然后,为了探讨终端移动对无线网络通信性能的影响,文中创建了一种新的基于2维终端速率分类与状态转换的移动模型,并且给出了相应的Markov分析方法.该模型能够更准确地反映用户移动规律,通过比较简单的参数学习来逼近3g/WLAN网络中终端的群体移动特征.最后,文中基于该模型对DLb-MSA机制进行性能评估,通过仿真验证了该机制的有效性.

关键词： b3g WLAN 动态负载均衡移动模型业务认知