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基于802.11 rts/cts策略的可用带宽测量方法

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电子技术应用 2015年第11期41卷 97-100页

作者：陈晟恺刘洪卜智勇中国科学院上海微系统与信息技术研究所上海200050

提出了一种改进的可用带宽估计方法。该方法通过加入信道利用率这一参数,保证了在不同Qo S条件下,可用带宽估计结果被新业务使用后不会影响网络中已有业务,从而能够真实反映信道可用带宽,而不是估计信道剩余容量。同时改进了ABE算法中... 详细信息

提出了一种改进的可用带宽估计方法。该方法通过加入信道利用率这一参数,保证了在不同Qo S条件下,可用带宽估计结果被新业务使用后不会影响网络中已有业务,从而能够真实反映信道可用带宽,而不是估计信道剩余容量。同时改进了ABE算法中碰撞概率以及退避过程消耗的带宽这两个参数,使得改进方法能够更加准确地估计IEEE 802.11 rts/cts策略中各种过程所带来的带宽消耗。

关键词： IEEE 802.11 rts/cts 可用带宽估计 Qo S保障

无线局域网基于终端的rts/cts呼叫准入控制

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中国新通信 2007年第17期9卷 20-22页

作者：关学攀北京交通大学北京100044

本片论文主要介绍了无线局域网中基于终端的呼叫准入控制机制。这个机制主要通过测量信道的利用率并且和先前的确定的门限进行比较,如果超过这个门限,则拒绝新的呼叫。这个机制的一个重要方面就是它还能用于隐藏终端的发现。主要是通过R... 详细信息

本片论文主要介绍了无线局域网中基于终端的呼叫准入控制机制。这个机制主要通过测量信道的利用率并且和先前的确定的门限进行比较,如果超过这个门限,则拒绝新的呼叫。这个机制的一个重要方面就是它还能用于隐藏终端的发现。主要是通过rts/cts的过程来决定新到的利用率。这个方法可以设计成更加动态。它可以和不同的数据速率协同合作。这个机制主要使用Qualnet网络方仿真器来模拟。一个经验方法会被用来确定一个合适的准入门限。然后,仿真会展现这个机制成功之处。

关键词：呼叫准人控制VoIP 802.11e rts/cts

无线网络MAC协议中rts/cts机制的研究

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郑州轻工业学院学报（自然科学版） 2008年第3期23卷 52-56页

作者：李娜娜甘勇贺蕾冯媛郑州轻工业学院计算机与通信工程学院河南郑州450002

从无线信道利用率的角度对无线局域网络的rts/cts机制进行性能仿真研究,发现数据包负荷较大时,机制对网络性能有正面影响,数据包负荷较小时;机制对网络性能有负面影响.在评判rts/cts机制在无线网络接入协议中的影响作用时,应将能量有效... 详细信息

从无线信道利用率的角度对无线局域网络的rts/cts机制进行性能仿真研究,发现数据包负荷较大时,机制对网络性能有正面影响,数据包负荷较小时;机制对网络性能有负面影响.在评判rts/cts机制在无线网络接入协议中的影响作用时,应将能量有效性作为系统主要性能指标.此外,还要考虑网络多跳的结构对机制的限制作用,从跨层优化的角度分析无线信道接入机制.

关键词： rts/cts CSMA/CA MAC 信道利用率

License Assisted Access-WiFi Coexistence with TXOP Backoff for LTE in Unlicensed Band

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China Communications 2017年第3期14卷 1-14页

作者： Salman Saadat Da Chen Kai Luo Mingjie Feng Tao Jiang School of Electronics Information and Communications Huazhong University of Science and Technology Wuhan 430074 China

License assisted access(LAA) was proposed as a solution to the challenge of satisfying high throughput requirement in cellular network with limited licensed band. LAA uses long term evolution(LTE) carrier aggregation technique to combine licensed and unlicensed bands, specifically 5 GHz Wi Fi band, in order to achieve high data rates. However, LAA has several critical concerns for services provision on 5 GHz unlicensed band. In this article, an overview of the techniques concerning the coexistence of LTE and Wi Fi on the same unlicensed band is presented. We first present several general approaches including power control of LTE evolved Node B(e NB), carrier selection, LTE duty cycling, self clear to send(cts) and request to send/cts(rts/cts), and listen before talk(LBT). Then, we focus on LBT techniques for LAA-Wi Fi coexistence and discuss how LBT based coexistence solutions can dynamically respond to the variations in network load and ensure fair coexistence in a distributed manner. Based on the LBT mechanism, we also present a fairness-aware LAA-WiF i coexisting scheme with TXOP(transmitted in a single transmission opportunity) backoff for LAA e NB. Finally, the performances of various LBT solutions for LAA-Wi Fi coexistence are evaluated using Markov chain analytical model.

关键词： LTE 共存 WiFi rts/cts Wi-Fi 接入聚合技术高数据速率

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实时监测无线传感器网络改进方法

交通运输工程学报 2012年第4期12卷 120-126页

作者：雷涛王松惠飞赵祥模长安大学信息工程学院陕西西安710064

结合危险品运输监测应用,搭建了基于无线传感器网络的实时监测系统,并对其MAC层协议和物理层无线数据发送时序进行了改进和优化。改进了MAC层中的原始BEB算法,引入了支持优先级的GDCF算法。对MAC层中的rts/cts方式进行了有效性分析,并... 详细信息

结合危险品运输监测应用,搭建了基于无线传感器网络的实时监测系统,并对其MAC层协议和物理层无线数据发送时序进行了改进和优化。改进了MAC层中的原始BEB算法,引入了支持优先级的GDCF算法。对MAC层中的rts/cts方式进行了有效性分析,并出于节能考虑,引入了睡眠技术。在物理层数据无线发送过程中,为缩短发送时间,减少碰撞可能性,对其时序进行了优化。在工程车辆上安装基于IRIS无线传感器的节点平台进行实际测试。测试结果表明:改进后的退避算法节点丢包率随网络节点数目增加变化不明显;去除rts/cts机制后,在采样间隔时间为50ms时,网络丢包率由20%左右下降到了6%以内;一个工作周期内节省能量达到95%;无线数据发送时序优化达到了设计要求,满足了实际应用中对实时监测无线传感网络的性能要求。

关键词：危险品运输无线传感器网络 MAC协议 GDCF rts/cts 物理层发送时序

Improving Throughput in Wireless Local Area Networks

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International Journal of Communications, Network and System Sciences 2008年第4期1卷 307-313页

作者： Imam AL-WAZEDI Anjali AGARWAL Ahmed K. ELHAKEEM Concordia University Montreal Quebec Canada

The medium access control (MAC) technique of standard WLANs, called the distributed coordination function (DCF), is carrier sense multiple access based on collision avoidance (CSMA/CA) scheme with binary slotted exponential backoff. It has a two way handshaking technique for packet transmission and also defines an additional four way handshaking technique called rts/cts mechanism, which is used to reduce the hidden terminal problem. The rts/cts frames carry the information of the packet length to be transmitted which can be read by any listening stations, to update a network allocation vector (NAV) about the information of the period of time in which the channel is busy. In this paper a method is proposed called the table driven technique (which has two parts called table driven DCF and table driven rts/cts) which is similar to the standard DCF (IEEE802.11) and rts/cts (IEEE802.11) system without having the exponential backoff. In this technique users use the optimum transmission probability by estimating the number of stations from the traffic conditions in a sliding window fashion one period at a time, thereby increasing the throughput compared to the standard DCF (IEEE802.11) and rts/cts (IEEE802.11) mechanism while maintaining the same fairness and the delay performance.

关键词： Standard DCF (IEEE802.11) Standard rts/cts (IEEE802.11) Table Driven DCF Table Driven rts/cts

Lightweight Robust Forwarding Scheme for Multi-Hop Wireless Networks

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International Journal of Communications, Network and System Sciences 2015年第3期8卷 19-28页

作者： Arif Sari Department of Management Information Systems European University of Lefke Lefke Cyprus

The Gossip-Based Relay Protocol (GRP) is developed based on Ad Hoc on Demand Distance Vector Protocol (AODV) and proposed to increase the efficiency of package routing functionality in ad hoc networks through specific flooding scheme. This lightweight protocol reduced the collisions on the network through specific mechanisms. Request to Send/Clear to Send (rts/cts) mechanism is widely used in ad hoc environment with Temporarily Ordered Routing Algorithm (TORA) in order to eliminate collisions and allow access to the shared medium through proposed authentication methods. Since GRP contains specific mechanism of directed acyclic Graph (DAG) mechanism to mitigate overhead problem, rts/cts modified TORA might result in similar performance metrics. In this paper, TORA protocol has a modification of new rts/cts mechanism and has been simulated in order to be compared with proposed lightweight robust forwarding GRP scheme in terms of specific performance metrics such as network throughput, end-to-end delay and message flooding rate over the network through OPNET simulation package in order to expose the optimal solution to increase overall network throughput in ad hoc environment.

关键词： GRP TORA rts/cts Mechanism OPNET Simulation Throughput Robust Forwarding Scheme

IEEE 802.11无线局域网中分布式协调功能的改进

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计算机应用 2005年第6期25卷 1257-1260页

作者：张亮舒炎泰天津大学电子信息工程学院天津300072

结合无线局域网和TCP的特点提出了一种改进算法,当AP向无线节点发数据包时,无线节点用一个小的数据包(如:TCP层的ACK等)来代替cts,这样可以避免无线节点单独发送小数据包,从而提高无线信道的利用率和无线网络的吞吐率。从试验结果可以看... 详细信息

结合无线局域网和TCP的特点提出了一种改进算法,当AP向无线节点发数据包时,无线节点用一个小的数据包(如:TCP层的ACK等)来代替cts,这样可以避免无线节点单独发送小数据包,从而提高无线信道的利用率和无线网络的吞吐率。从试验结果可以看出,改进后的DCF协议不仅提高了信道的利用率和无线局域网的性能,而且更好的维护了无线节点间的公平性。

关键词： IEEE 802.11 无线局域网分布式协调功能 rts/cts

Modeling and Analysis of Wireless Controller Area Network—A Review

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Communications and Network 2013年第2期5卷 126-133页

作者： Gerardine Immaculate Mary Z. C. Alex Lawrence Jenkins School of Electronics Engineering VIT University Vellore India

This paper reviews the research work done on the Modeling and Analysis of Wireless Controller Area Network (WCAN). The controller area network (CAN) has been long regarded as the pioneer in standardizing vehicle bus standard. Its influence has even been reached out to various applications in industrial automation;which includes military, aviation, electronics and many others. With wireless technology becoming more pervasive, there is also a need for CAN too to migrate and evolve to its wireless counterpart [1]. A few methods were proposed in the last decade [2-6] that utilized the advantageous of CAN into a wireless network system called wireless controller area network (WCAN). This paper reviews these approaches of WCAN.

关键词： Wireless CAN Modeling and Analysis WTRP rts/cts WCAN