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A CSMA/CA based MAC protocol for hybrid Power-line/Visible-light communication networks:Design and analysis
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作者 Sheng Hao Huyin Zhang +2 位作者 Fei Yang Chenghao Li Jing Wang 《Digital Communications and Networks》 SCIE CSCD 2024年第2期481-497,共17页
Hybrid Power-line/Visible-light Communication(HPVC)network has been one of the most promising Cooperative Communication(CC)technologies for constructing Smart Home due to its superior communication reliability and har... Hybrid Power-line/Visible-light Communication(HPVC)network has been one of the most promising Cooperative Communication(CC)technologies for constructing Smart Home due to its superior communication reliability and hardware efficiency.Current research on HPVC networks focuses on the performance analysis and optimization of the Physical(PHY)layer,where the Power Line Communication(PLC)component only serves as the backbone to provide power to light Emitting Diode(LED)devices.So designing a Media Access Control(MAC)protocol remains a great challenge because it allows both PLC and Visible Light Communication(VLC)components to operate data transmission,i.e.,to achieve a true HPVC network CC.To solve this problem,we propose a new HPC network MAC protocol(HPVC MAC)based on Carrier Sense Multiple Access/Collision Avoidance(CSMA/CA)by combining IEEE 802.15.7 and IEEE 1901 standards.Firstly,we add an Additional Assistance(AA)layer to provide the channel selection strategies for sensor stations,so that they can complete data transmission on the selected channel via the specified CSMA/CA mechanism,respectively.Based on this,we give a detailed working principle of the HPVC MAC,followed by the construction of a joint analytical model for mathematicalmathematical validation of the HPVC MAC.In the modeling process,the impacts of PHY layer settings(including channel fading types and additive noise feature),CSMA/CA mechanisms of 802.15.7 and 1901,and practical configurations(such as traffic rate,transit buffer size)are comprehensively taken into consideration.Moreover,we prove the proposed analytical model has the solvability.Finally,through extensive simulations,we characterize the HPVC MAC performance under different system parameters and verify the correctness of the corresponding analytical model with an average error rate of 4.62%between the simulation and analytical results. 展开更多
关键词 Hybrid power-line/Visible light communication (HPVC)networks MAC protocol CSMA/CA IEEE 802.15.7 IEEE 1901 Performance analysis
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Priority Based Energy Efficient MAC Protocol by Varying Data Ratefor Wireless Body Area Network
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作者 R.Sangeetha Usha Devi Gandhi 《Computer Systems Science & Engineering》 2024年第2期395-411,共17页
Wireless Body Area Network(WBAN)is a cutting-edge technology that is being used in healthcare applications to monitor critical events in the human body.WBAN is a collection of in-body and on-body sensors that monitor ... Wireless Body Area Network(WBAN)is a cutting-edge technology that is being used in healthcare applications to monitor critical events in the human body.WBAN is a collection of in-body and on-body sensors that monitor human physical parameters such as temperature,blood pressure,pulse rate,oxygen level,body motion,and so on.They sense the data and communicate it to the Body Area Network(BAN)Coordinator.The main challenge for the WBAN is energy consumption.These issues can be addressed by implementing an effective Medium Access Control(MAC)protocol that reduces energy consumption and increases network lifetime.The purpose of the study is to minimize the energy consumption and minimize the delay using IEEE 802.15.4 standard.In our proposed work,if any critical events have occurred the proposed work is to classify and prioritize the data.We gave priority to the highly critical data to get the Guarantee Tine Slots(GTS)in IEEE 802.15.4 standard superframe to achieve greater energy efficiency.The proposed MAC provides higher data rates for critical data based on the history and current condition and also provides the best reliable service to high critical data and critical data by predicting node similarity.As an outcome,we proposed a MAC protocol for Variable Data Rates(MVDR).When compared to existing MAC protocols,the MVDR performed very well with low energy intake,less interruption,and an enhanced packet-sharing ratio. 展开更多
关键词 Wireless Body Area Network(WBAN) IEEE 802.15.4 energy efficiency MAC protocol ZIGBEE
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基于IEEE 802.1AS的多跳时钟同步算法与系统实现
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作者 赵国锋 危瑞鹏 +2 位作者 邢媛 徐川 张汝凤 《电子学报》 EI CAS CSCD 北大核心 2024年第3期814-823,共10页
针对现有IEEE 802.1AS协议中单一主时钟无法保障多跳网络下高精度同步的问题,提出一种基于多属性决策的冗余时钟同步方法.首先,基于链路拥塞程度、节点拓扑属性和时钟源质量系数对时钟属性值进行建模;其次,采用多属性决策算法选取最佳... 针对现有IEEE 802.1AS协议中单一主时钟无法保障多跳网络下高精度同步的问题,提出一种基于多属性决策的冗余时钟同步方法.首先,基于链路拥塞程度、节点拓扑属性和时钟源质量系数对时钟属性值进行建模;其次,采用多属性决策算法选取最佳主时钟并生成冗余时钟序列表;最后,利用FPGA(Field Programmable Gate Array)平台设计并实现冗余时钟同步系统,同时搭建真实网络环境对所提方法进行测试.结果表明,相较于现有方法,时钟同步精度提升了68%,主时钟失效后重新同步所需收敛时间减小了60%. 展开更多
关键词 时钟同步 IEEE 802.1AS协议 主时钟选取 冗余时钟 FPGA
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基于PER-DDPG算法的城市轨道交通越区切换研究
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作者 张军平 王小鹏 王冶力 《山西电子技术》 2024年第3期100-102,共3页
针对传统IEEE802.11越区切换方式存在较高的切换延时以及乒乓切换等问题,提出深度强化学习(Deep Q-Network,DQN)越区切换算法。通过对列车运行的特征状态信息进行提取输入,考虑列车运行速度及场强、切换阈值等动态信息构建越区切换模型... 针对传统IEEE802.11越区切换方式存在较高的切换延时以及乒乓切换等问题,提出深度强化学习(Deep Q-Network,DQN)越区切换算法。通过对列车运行的特征状态信息进行提取输入,考虑列车运行速度及场强、切换阈值等动态信息构建越区切换模型。同时针对算法时间成本复杂度及稳定性,采用优先经验回放深度确定性策略梯度(Prioritized Experience Replay-Deep Deterministic Policy Gradient,PER-DDPG)算法,将列车状态空间信息传输至PER-DDPG网络中进行优化分析。结果表明基于PER-DDPG算法优化后的列车越区切换模型使用该算法时间计算成本降低,数据包传输延时约降低55%。 展开更多
关键词 基于通信列车控制 CBTC系统 IEEE802.11标准 优先经验回放机制深度确定策略梯度算法
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IEEE802.11i无线局域网安全标准分析 被引量:10
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作者 沈敦厚 彭江宇 +1 位作者 胡博 龚发根 《计算技术与自动化》 2004年第4期106-108,共3页
随着无线网络的蓬勃发展,无线网络的安全问题引起了越来越多的企业、组织和个人的关注。该文对刚推出的IEEE802.11i无线局域网安全标准进行了全面系统的分析,最后指出了其仍存在的一些问题。
关键词 ieee802.11i 无线局域网安全 无线网络 安全问题 企业 发展 个人 系统 组织 标准
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两种无线局域网安全标准WAPI与IEEE802.11i的比较 被引量:3
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作者 朱坤华 王玉芬 李新丽 《河南科技学院学报》 2005年第1期83-85,共3页
本文从两个标准的技术实质与工作原理两方面来加以分析和比较,并在文末预测了它们的前景。
关键词 无线局域网 WAPI IEEE 802.11i TKIP AES
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IEEE802.11i安全机制分析与实现 被引量:1
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作者 朱敏 《电脑知识与技术》 2009年第4X期3094-3095,3102,共3页
研究了IEEE802.11i协议的安全机制,对IEEE802.11i强安全网络连接的安全性进行了分析,并在实际网络平台中对其进行实现与验证。
关键词 无线局域网 ieee802.11i协议 安全机制 强安全网络
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Wi-Fi 7技术与产业发展探讨
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作者 陈洁 《通信世界》 2024年第3期16-17,共2页
Wi-Fi网络已成为人们日常生活中不可或缺的一部分。家庭场景中手机、平板电脑、摄像头、智能家电等终端均连接到Wi-Fi网络;商场、机场、酒店等公共场所处处可见提供定位、导航和移动支付等业务的免费Wi-Fi网络;在企业园区内,用户通过Wi... Wi-Fi网络已成为人们日常生活中不可或缺的一部分。家庭场景中手机、平板电脑、摄像头、智能家电等终端均连接到Wi-Fi网络;商场、机场、酒店等公共场所处处可见提供定位、导航和移动支付等业务的免费Wi-Fi网络;在企业园区内,用户通过Wi-Fi网络实现移动协同办公。目前Wi-Fi技术已经演进到第七代,即遵循IEEE802.11be标准的Wi-Fi 7。Wi-Fi7的设计目标是利用现有的2.4GHZ、5GHz以及新增的6GHZ频段,兼顾高性能和高可靠两方面特性,使得Wi-Fi速率达到30Gbit/s以上,时延降低到5ms以下。基于时延、速率和容量等方面的优势,Wi-Fi7有望应用于扩展现实(XR)、元宇宙、社交游戏和边缘计算等高速率、超低时延应用场景。 展开更多
关键词 IEEE802.11B 边缘计算 移动支付 平板电脑 智能家电 低时延 技术与产业发展 企业园区
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IEEE802.11i中四次握手过程的安全分析和改进 被引量:5
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作者 梁峰 史杏荣 曲阜平 《计算机工程》 CAS CSCD 北大核心 2007年第3期149-150,179,共3页
对IEEE802.11i协议中四次握手过程的临时会话密钥的协商和建立过程中的安全性进行了分析,发现在四次握手过程中存在安全隐患,并因此可能受到DoS(拒绝服务)攻击。在此基础上提出了一种改进方法,使四次握手过程的安全性得到进一步增强。
关键词 无线局域网 ieee802.11i协议 四次握手 拒绝服务 密钥管理
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基于TSCH的工业无线网络流量自适应传输调度机制研究
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作者 闫明月 裘莹 《智能计算机与应用》 2024年第5期164-171,共8页
当今LLN网络设备要满足低功耗要求的同时必须支持多种业务数据的传输,所以需要一种动态调度算法提高网络的可靠性。虽然基于IEEE 802.15.4标准的时隙信道跳变(TSCH)技术可以满足LLN的需求,然而现有的TSCH调度算法缺少灵活性。为了解决... 当今LLN网络设备要满足低功耗要求的同时必须支持多种业务数据的传输,所以需要一种动态调度算法提高网络的可靠性。虽然基于IEEE 802.15.4标准的时隙信道跳变(TSCH)技术可以满足LLN的需求,然而现有的TSCH调度算法缺少灵活性。为了解决这一问题,本文提出了基于TSCH的流量感知自适应调度改进算法(Enhanced Adaptive Transmission Scheduling Mechanism,EATSM)。本文通过自相似性采样方法采集各链路流量信息,在准确获取各个邻居链路流量之后进行按权按序为每个邻居链路分配时隙数量与位置,保证传输可靠性的同时又能做到调度灵活性。通过理论分析与实验数据对比,本文提出的EATSM调度算法设计相比较于主流自适应调度算法,数据包投递率为99.57%,提高了0.26个百分点,节点运行占空比为0.34%,减少了0.88个百分点。 展开更多
关键词 LLN IEEE 802.15.4 TSCH 动态时隙调度 无线网络协议
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用分布式时序逻辑形式化分析IEEE802.11i协议
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作者 杨琳琳 周勇 《南通大学学报(自然科学版)》 CAS 2010年第3期24-30,共7页
基于Caleiro提出的分布式时序逻辑,在其模型中增加了挑战问题集合和挑战应答集合,将IEEE802.11i协议转化为分布式时序逻辑的事件结构语义模型.形式化分析并证明了该协议的保密性以及协议中申请者、认证者、认证服务器之间的相互认证性.... 基于Caleiro提出的分布式时序逻辑,在其模型中增加了挑战问题集合和挑战应答集合,将IEEE802.11i协议转化为分布式时序逻辑的事件结构语义模型.形式化分析并证明了该协议的保密性以及协议中申请者、认证者、认证服务器之间的相互认证性.结果表明,IEEE802.11i协议是安全的. 展开更多
关键词 分布式时序逻辑 形式化分析 ieee802.11i协议 网络模型
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ARROW-WTCP:A fast transport protocol based on explicit congestion notification over wired/wireless networks 被引量:3
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作者 王建新 李婧 荣亮 《Journal of Central South University》 SCIE EI CAS 2011年第3期800-808,共9页
An explicit congestion notification (ECN)-based distributed transport protocol,ARROW-WTCP (AcceleRate tRansmission towards Optimal Window size TCP for Wireless network),was proposed.The ARROW-WTCP enables feasible dep... An explicit congestion notification (ECN)-based distributed transport protocol,ARROW-WTCP (AcceleRate tRansmission towards Optimal Window size TCP for Wireless network),was proposed.The ARROW-WTCP enables feasible deployment of ARROW-TCP from wired to wireless networks by providing a joint design of source and router algorithms.The protocol obtains the actual capacity of the wireless channel by calculating the queue variation in base station (BS) and adjusts the congestion window by using the feedback from its bottleneck link.The simulation results show that the ARROW-WTCP achieves strong stability,max-min fairness in dynamic networks,fast convergence to efficiency without introducing much excess traffic,and almost full link utilization in the steady state.It outperforms the XCP-B (eXplicit Control Protocol Blind),the wireless version of XCP,in terms of stability,fairness,convergence and utilization in wireless networks. 展开更多
关键词 网络传输协议 显式拥塞通知 无线网络 箭头 有线 拥塞窗口 链路利用率 联合设计
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基于扩展串空间模型的IEEE802.11i分析
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作者 操漫成 《计算机工程》 CAS CSCD 北大核心 2009年第10期126-128,131,共4页
通过对串空间模型的扩展,使其具备分析复杂安全协议的能力。利用扩展后的串空间模型,对IEEE802.11i协议中的4步握手协议进行分析,证明4步握手协议达到协议机密性和认证正确性目标的结论。指出在协议可用性分析方面还须继续对分析方法进... 通过对串空间模型的扩展,使其具备分析复杂安全协议的能力。利用扩展后的串空间模型,对IEEE802.11i协议中的4步握手协议进行分析,证明4步握手协议达到协议机密性和认证正确性目标的结论。指出在协议可用性分析方面还须继续对分析方法进行扩展研究。 展开更多
关键词 串空间 ieee802.11i协议 安全协议
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RATE ADAPTIVE PROTOCOL FOR MULTIRATE IEEE 802.11 NETWORKS 被引量:1
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作者 Xi Yong Huang Qingyan +1 位作者 Wei Jibo Zhao Haitao 《Journal of Electronics(China)》 2007年第3期289-295,共7页
In this paper, a rate adaptive protocol AMARF (Adaptive Multirate Auto Rate Fallback) for multirate IEEE 802.11 networks is proposed. In AMARF, each data rate is assigned a unique success threshold, which is a criteri... In this paper, a rate adaptive protocol AMARF (Adaptive Multirate Auto Rate Fallback) for multirate IEEE 802.11 networks is proposed. In AMARF, each data rate is assigned a unique success threshold, which is a criterion to judge when to switch a rate to the next higher one, and the success thresholds can be adjusted dynamically in an adaptive manner according to the running conditions, such as packet length and channel parameters. Moreover, the proposed protocol can be implemented by software without any change to the current IEEE 802.11 standards. Simulation result shows that AMARF yields significantly higher throughput than other existing schemes including ARF and its variants, in various running conditions. 展开更多
关键词 速率自适应协议 多速率网络 IEEE802.11 信道参数
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Adaptive Backoff Algorithm for IEEE 802.11 MAC Protocol 被引量:1
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作者 Maali ALBALT Qassim NASIR 《International Journal of Communications, Network and System Sciences》 2009年第4期300-317,共18页
A Mobile Ad Hoc Network (MANET) is a collection of mobile nodes that can communicate directly over wireless media, without the need for a preconfigured infrastructure. Several approaches have been suggested to improve... A Mobile Ad Hoc Network (MANET) is a collection of mobile nodes that can communicate directly over wireless media, without the need for a preconfigured infrastructure. Several approaches have been suggested to improve Quality of Service (QoS) in IEEE 802.11-based MANETs through modifying some of the IEEE 802.11 Medium Access Control (MAC) algorithms, such as the backoff algorithm that is used to control the packets collision aftermath. In this work, an adaptive IEEE 802.11 backoff algorithm to improve QoS is de-veloped and tested in simulations as well as in testbed implementation. While the Binary Exponential Backoff (BEB) algorithm deployed by IEEE 802.11 reacts based on individual packet transmit trials, the new algo-rithm takes the history of successive packet transmit trials into account to provide a better QoS performance. The new algorithm has been tested against the legacy IEEE 802.11 through simulations using QualNet and a Linux-based testbed comprising a number of stations. The performed tests have shown significant im-provements in performance, with up to 33.51% improvement in delay and 7.36% improvement in packet delivery fraction compared to the original IEEE 802.11. 展开更多
关键词 MANETS AD-HOC Networks Quality of Service BACKOFF Algorithm IEEE 802.11
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浅析IEEE802.11i标准的改进及运营问题
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作者 田文娟 许恒 《江苏广播电视大学学报》 2005年第3期74-75,共2页
针对IEEE802.11标准在数据加密和身份认证两方面存在的设计缺陷,IEEE802.11i标准进行了相应改进,较好地解决了存在的问题,但IEEE802.11i在运行中也可能存在一些问题。
关键词 无线局域网安全协议 ieee802.11i 运营难点
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Key Management Protocol of the IEEE 802.16e
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作者 TIAN Haibo PANG Liaojun WANG Yumin 《Wuhan University Journal of Natural Sciences》 CAS 2007年第1期59-62,共4页
IEEE 802.16e, as an amendment and corrigendum to the IEEE 802.16-2004, published on 28 February 2006, and intended to update and expand IEEE 802.16-2004 to allow for mobile subscriber stations. This paper summarizes t... IEEE 802.16e, as an amendment and corrigendum to the IEEE 802.16-2004, published on 28 February 2006, and intended to update and expand IEEE 802.16-2004 to allow for mobile subscriber stations. This paper summarizes the key management protocol belonging to security part of the IEEE 802.16e, which includes security negotiation, authorization, key derivation, handshake, and key transportation. While these building blocks are well designed, we point out some unwelcome features for these building blocks. We also give out suggestions to diminish the proposed problems. 展开更多
关键词 IEEE 802.16e security analysis key management protocol
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MAC Frame Resolution and PHY Protocol Type Detection of IEEE 802.11
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作者 Ling Li Shi Peng +5 位作者 June Li Kai Yuan Zhihao Wang Yinbin Liu Ping Chen Xianbing Wang 《International Journal of Communications, Network and System Sciences》 2017年第5期43-53,共11页
Frame resolution and physical layer (PHY) protocol type detection are the basis of research and development of intrusion prevention systems for IEEE 802.11 wireless network. Aiming at the problems which cannot be solv... Frame resolution and physical layer (PHY) protocol type detection are the basis of research and development of intrusion prevention systems for IEEE 802.11 wireless network. Aiming at the problems which cannot be solved by the specifications export, this paper proposed a MAC frame analytical method and a PHY protocol type detection algorithm based on parsing the IEEE 802.11packets captured by the library Libpcap. The packet structure and the length of the frame preamble (18 or 26 bytes) are presented. Then the methods of transforming byte-order and resolving sub-fields are given. A detection algorithm of PHY protocol type is proposed based on the experiments and examples are given to verify these methods. This work can be a reference for the R & D related to link layer frame analysis. 展开更多
关键词 IEEE 802.11 MAC FRAME RESOLUTION PHY protocols DETECTION
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FMAC: Fair Mac Protocol for Achieving Proportional Fairness in Multi-Rate WSNs
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作者 Nusaibah M. Al-Ratta Mznah Al-Rodhaan Abdullah Al-Dhelaan 《Communications and Network》 2015年第2期89-105,共17页
In a multi-rate wireless environment, slow nodes occupy the channel for longer time than fast nodes and thus the total throughput of the network will be reduced. In this research, we study the problem of fairness in m... In a multi-rate wireless environment, slow nodes occupy the channel for longer time than fast nodes and thus the total throughput of the network will be reduced. In this research, we study the problem of fairness in multi-rate wireless sensor networks. To improve the fairness, we propose a new protocol, FMAC (Fair MAC protocol) that is based on IEEE 802.11 MAC protocol to achieve proportional fairness between all nodes. FMAC protocol includes medium delay periods within Backoff algorithm to utilize the idle slots of time and reduce the number of collisions and then number of retransmissions, and thus reducing the energy consumption, which is very critical in wireless sensor networks. The experimental results show that transmissions become faster with less collisions and power consumption when applying FMAC, while the aggregated throughput and proportional fairness are increased. The detailed performance evaluation and comparisons are provided using the simulation. 展开更多
关键词 BACKOFF DCF IEEE 802.11 Proportional FAIRNESS Wireless Sensor Networks
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An Energy-Efficient MAC Protocol for Ad Hoc Networks
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作者 Yongsheng SHI T. Aaron GULLIVER 《Wireless Sensor Network》 2009年第5期407-416,共10页
A mobile ad hoc network (MANET) is a collection of nodes equipped with wireless communications and a networking capability without central network control. Nodes in a MANET are free to move and organize themselves in ... A mobile ad hoc network (MANET) is a collection of nodes equipped with wireless communications and a networking capability without central network control. Nodes in a MANET are free to move and organize themselves in an arbitrary fashion. Energy-efficient design is a significant challenge due to the characteristics of MANETs such as distributed control, constantly changing network topology, and mobile users with limited power supply. The IEEE 802.11 MAC protocol includes a power saving mechanism, but it has many limitations. A new energy-efficient MAC protocol (EE-MAC) is proposed in this paper. It is shown that EE-MAC performs better than IEEE 802.11 power saving mode and exceeds IEEE 802.11 with respect to balancing network throughput and energy savings. 展开更多
关键词 ENERGY-EFFICIENT MAC protocol IEEE 802.11 Ad HOC Networks
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