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基于自适应帧聚合机制的无线局域网吞吐量分析

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东南大学学报（自然科学版） 2011年第4期41卷 665-671页

作者：沈丹萍沈连丰吴名鲍楠孙元凯王欣东南大学移动通信国家重点实验室南京210096

在分析IEEE 802.11n中A-MSDU和A-MPDU两种MAC层帧聚合机制的基础上,针对MAC层帧聚合中子帧必须使用相同调制编码方式以及具有最大帧长限制的问题,引入物理层超帧,并采用自适应帧聚合机制来改善系统的吞吐量性能.推导了有扰信道下采用DC... 详细信息

在分析IEEE 802.11n中A-MSDU和A-MPDU两种MAC层帧聚合机制的基础上,针对MAC层帧聚合中子帧必须使用相同调制编码方式以及具有最大帧长限制的问题,引入物理层超帧,并采用自适应帧聚合机制来改善系统的吞吐量性能.推导了有扰信道下采用DCF接入机制时各类帧聚合以及帧分段方式在饱和状态的吞吐量,讨论了网络站点数、帧长度、接入模式对吞吐量的影响,分析了DCF接入机制下成功接收的帧延时和延时要求对最大聚合帧数的限制.仿真结果表明,在特定误比特率和延时要求下,所提出的自适应帧聚合机制可以通过选择合适的帧聚合或帧分段方式使吞吐量最大化.

关键词：无线局域网吞吐量帧聚合物理层超帧

Cooperative algorithm for improving network connectivity in clustered wireless sensor networks

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Journal of Southeast University(English Edition) 2011年第1期27卷 1-7页

作者：李文峰邵震洪沈连丰东南大学移动通信国家重点实验室南京210096

In order to improve network connectivity in clustered wireless sensor networks,a node cooperative algorithm based on virtual antenna arrays is *** the nodes in the network are assumed to be clustered via Poisson Voronoi tessellation（PVT）.The activation of the node cooperative algorithm is determined by the cluster heads（CHs） according to communication *** the cooperative algorithm is activated,the CH selects cooperative nodes（CNs） from its members to form a virtual antenna *** the cooperation,nodes can extend the inter-cluster communication range to directly contact with further nodes after a coverage hole is detected,or compensate for channel gains while inter-cluster transmission fails due to deep channel *** results show that the proposed algorithm achieves better network connectivity and energy *** can reduce outage probability,sustain network connectivity and maintain operations as long as possible,which prolongs network operation time.

关键词： wireless sensor network coverage cooperative communication operation time

Dependent task assignment algorithm based on particle swarm optimization and simulated annealing in ad-hoc mobile cloud

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Journal of Southeast University(English Edition) 2018年第4期34卷 430-438页

作者： Huang Bonan Xia Weiwei Zhang Yueyue Zhang Jing Zou Qian Yan Feng shen lianfeng National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China

In order to solve the problem of efficiently assigning tasks in an ad-hoc mobile cloud( AMC),a task assignment algorithm based on the heuristic algorithm is proposed. The proposed task assignment algorithm based on particle swarm optimization and simulated annealing( PSO-SA) transforms the dependencies between tasks into a directed acyclic graph( DAG) model. The number in each node represents the computation workload of each task and the number on each edge represents the workload produced by the transmission. In order to simulate the environment of task assignment in AMC,mathematical models are developed to describe the dependencies between tasks and the costs of each task are defined. PSO-SA is used to make the decision for task assignment and for minimizing the cost of all devices,which includes the energy consumption and time delay of all ***-SA also takes the advantage of both particle swarm optimization and simulated annealing by selecting an optimal solution with a certain probability to avoid falling into local optimal solution and to guarantee the convergence speed. The simulation results show that compared with other existing algorithms,the PSO-SA has a smaller cost and the result of PSO-SA can be very close to the optimal solution.

关键词： ad-hoc mobile cloud task assignment algorithm directed acyclic graph particle swarm optimization simulated annealing

基于接入选择和业务转移的异构网络动态负载均衡机制

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高技术通讯 2014年第10期24卷 1007-1013页

作者：朱思峰沈连丰柴争义东南大学移动通信国家重点实验室南京210096 周口师范学院数学与统计学院周口466001

为了提高异构网络系统的整体性能,提出了一种基于接入选择和业务转移的动态负载均衡机制。给出了接入选择问题的优化模型,通过求解模型得到了最优接入选择方案,根据接入选择方案把接入任务均衡地分配到各个基站小区中。为了削弱热点小... 详细信息

为了提高异构网络系统的整体性能,提出了一种基于接入选择和业务转移的动态负载均衡机制。给出了接入选择问题的优化模型,通过求解模型得到了最优接入选择方案,根据接入选择方案把接入任务均衡地分配到各个基站小区中。为了削弱热点小区突发性业务对系统负载均衡性的破坏,给出了基于基站负载率阈值的业务转移方案。仿真实验结果表明,提出的动态负载均衡方案在接入阻塞率、切换掉线率、负载均衡性、系统利用率4个指标上的表现均优于已有文献报道的方案,具有较好的应用价值。

关键词：异构无线网络负载均衡接入选择业务转移网络资源管理

Text　and　Voice　Integrated　Paging　System

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Journal of Southeast University(English Edition) 1996年第1期12卷 12-18页

作者： shen lianfeng Wei Huihai Wan Shan(National Communications Research Laboratory, Department of Radio Engineering,Southeast University,Nanjing 210018)

In this paper,the key techniques and approaches to pragmatize text and voice integrated paging system are discussed. Based on the analyses, a 2 400 bps integrated experimental paging system fully compatible with P... 详细信息

关键词： integrated paging system voice processing card paging station pager encode decode

A priority-based dynamic load transfer algorithm for cellular/WLAN integrated networks

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Journal of Southeast University(English Edition) 2012年第1期28卷 14-20页

作者：陈赓夏玮玮许波沈连丰东南大学移动通信国家重点实验室南京210096 中国人民解放军理工大学通信工程学院南京210016

For the integration network of a cellular network and a wireless local area network （WLAN）, a priority-based dynamic load transfer （PDLT） algorithm is proposed. The dynamic vertical handoffs by call admission control are jointly determined by the network conditions and the traffic characteristics in combination with the location-condition of mobile terminals. When there is no bandwidth resource available in the cellular network or WLAN, the proposed PDLT algorithm allows an incoming voice call or data call within the overlapping area of the cellular network and the WLAN to be directed to the spare network; meanwhile, by dynamically computing the occupancy of the bandwidth resource, the proposed PDLT algorithm also allows an ongoing voice call or data communication to be transferred to the network with a sufficient bandwidth resource according to the given threshold to balance the number of voice/data calls in the two networks. The analysis results of a two-dimensional Markov model and the simulation results show that the PDLT algorithm can effectively enhance the whole integrated network＇ s traffic, reduce the blocking probability of new calls and increase the data throughput, and thus decrease the response time for various services.

关键词： cellular network WLAN dynamic load transfer blocking probability Markov model

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蓝牙Ad Hoc网络的路由实现及优化

东南大学学报（自然科学版） 2005年第4期35卷 501-505页

作者：谷金山沈连丰苏红平邱晓华东南大学移动通信国家重点实验室南京210096 江苏紫金电子集团有限公司南京210028

为了在蓝牙系统实现多跳的移动AdHoc网络,考虑到蓝牙设备存储容量较小、处理能力较弱的缺点,根据蓝牙主从通信、轮询接入以及时分双工的技术特点,给出了蓝牙AdHoc网络的路由协议设计思想以及实现方法.分析和仿真的结果表明对蓝牙微微网... 详细信息

为了在蓝牙系统实现多跳的移动AdHoc网络,考虑到蓝牙设备存储容量较小、处理能力较弱的缺点,根据蓝牙主从通信、轮询接入以及时分双工的技术特点,给出了蓝牙AdHoc网络的路由协议设计思想以及实现方法.分析和仿真的结果表明对蓝牙微微网中设备的MAC地址和LocID增加一位可以有效地解决网络中存在主从复合节点单元时可能会引起的路由混淆问题;主从设备各自维护本微微网内所有设备的属性可以显著地减少路由发现的时间并且增加路由发现的概率.该方法可以很好地解决蓝牙节点不能作为一个独立的AdHoc节点工作的问题.

关键词：蓝牙 Ad Hoc 路由

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基于盲源分离的无线视频通信研究与仿真

东南大学学报（自然科学版） 2007年第1期37卷 13-17页

作者：郭洁沈连丰宋铁成叶芝慧东南大学移动通信国家重点实验室南京210096

提出了一种多路视频压缩信号在无线信道中的盲源分离解决方案.该方案选用IEEE802.11b作为无线通信标准及XviD作为MPEG-4视频压缩方法,建立了一个MPEG-4无线视频传输系统及其仿真模型.该模型用盲源分离方法来解决多个视频信号的分离问题... 详细信息

提出了一种多路视频压缩信号在无线信道中的盲源分离解决方案.该方案选用IEEE802.11b作为无线通信标准及XviD作为MPEG-4视频压缩方法,建立了一个MPEG-4无线视频传输系统及其仿真模型.该模型用盲源分离方法来解决多个视频信号的分离问题.仿真通过多次比较得出一种基于信号循环平稳性的NWCW-CS,其分离效果最佳及收敛速度最快.仿真结果还表明,该算法可以很好地解决视频信号的混叠问题,视频信号由XviD解压后的图像与原先一致,同时满足视频传输的实时性要求.

关键词：盲源分离循环平稳视频 MPEG-4 无线局域网

Interference analysis and improvement of capacity reduction for FHSS networks in WPAN application environment

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Journal of Southeast University(English Edition) 2003年第3期19卷 205-211页

作者：叶芝慧沈连丰宋铁成东南大学移动通信国家重点实验室

The coexistence between Bluetooth system and IEEE 802.11 frequency hoppingspread spectrum (FHSS) equipment is analyzed. Based on the capacity formulae and system simulation,the inter-affection between these networks is compared. A fragment adaptive solution of packetpayload length is presented, which can be used to improve the capacity reduction of IEEE 802.11 FHSSnetwork. Analysis results show that the IEEE 802.11 WLAN standard with its inherent mechanismsupports this fragment length adaptive algorithm. With the increasing of Bluetooth interferingnetworks, this adaptive solution can effectively relieve capacity decreasing of IEEE 802.11 FHSSnetwork. The capacity analysis method and adaptive algorithm adopted in this paper can also begeneralized into other FHSS networks.

关键词： WPAN frequency-hopping network capacity bluetooth technology IEEE 802.11FHSS network fragment adaptive of packet payload length