几种IEEE802.11无线局域网协议的比较

WLAN的出现，充分解决了有线网络先天性缺陷所带来的一系列问题。与有线网络相比，WLAN具备了很多特定优势。作为有线局域网的一种补充和扩展，WALN使计算机具有了可移动性，能快速、方便地解决有线网络不易实现的网络连通问题，成为今后网络发展的主导方向。IEEE802．11标准是IEEE制定的无线局域网标准，各厂商的产品在同一物理层上可以互相操作，这样就使得无线局域网的两种主要用途“多点接入”和“多网段互联”更易于低成本实现，从而为无线局域网的进一步普及打通了道路，文中介绍了几个常用标准的特点。     

IEEE802.11无线局域网标准

介绍了IEEE802.11无线局域网技术规范.给出了ISM频段、扩频技术的背景及各国相应的标准、规范.描述了允许可证2.4GHzISM频段的直接序列扩频技术及IEEE802.11协议规范。     

IEEE 802.11g系统综述及关键技术分析

介绍了无线局域网(WLAN)领域存在的多种技术标准,着重对IEEE802.11系列WLAN标准进行了对比分析,叙述了IEEE802.11g标准的概念、产生背景、特点及其体系结构,探讨了IEEE802.11g在实现高速通信的同时兼顾后向兼容性所采用的关键技术,探讨了IEEE802.11g实用化需要解决的重点问题及其解决方案,最后重点介绍了IEEE802.11g双频多模工作的实现方案及其发展前景。     

IEEE802.11标准及无线局域网技术

由于无线局域网所具有的优势，它不仅将在广电系统的办公自动化和智能化中发挥积极的作用，而且也将可能在视音频数据的传输中得到应用。本详细介绍了无线局域网概念、相关标准内容、所涉及的协议、组网方式以及相关传输技术。     

IEEE 802.11g性能分析及应用

全面介绍IEEE802.11g标准的无线局域网,详细讲述IEEE802.11g草案标准的概念、产生背景、特点、构件及其体系结构和发展前景,探讨实现IEEE802.11gWLAN所需的关键技术及其双频多模应用方式,同时分析IEEE802.11g标准的网络性能。     

IEEE802.11a及无线局域网技术

由于无线局域网所具有的优势，它不仅将在广电系统的办公自动化和智能化中发挥积极的作用，而且也将可能在视音频数据的传输中得到应用。本文详细介绍了无线局域网概念，相关标准内容、所涉及的协议，组网方式以及相关传输技术。     

IEEE 802.11无线局域网标准发展历程及其发展方向

本详细介绍了IEEE802．11标准组成，标准发展历程和发展方向。     

IEEE802.11无线局域网中的Qos机制

无线局域网（WLAN）是对目前无线接入系统的补充，可以使网络用户摆脱网线的束缚，实现真正意义上的移动互联。与蜂窝系统相比，它的户外移动性虽然受到限制，但适用面广，可在典型的应用环境如办公室、家庭、展览厅、机场、火车站等热点地区，向终端用户提供高速数据传输。WLA     

IEEE802.11g协议关键技术与性能分析鲻

本文介绍了无线局域网最新发展802.11g协议的产生背景、概念、特点及协议技术细节,详细讲述了11g协议的帧格式,探讨了实现11g协议的几项关键技术,并对网络性能的提升进行了分析.     

IEEE 802.11无线局域网的关联过程

本文介绍了IEEE 802.11无线局域网中站点与AP建立关联关系的过程,并详细分析了不同MAC帧所包含的无线网络信息,对指导网络维护优化具有重要价值。     

IEEE 802.11s: WLAN mesh standardization and high performance extensions

In recent years, remarkable market competition and economy of scale has resulted in the price erosion of wireless devices for consumer electronics. Especially for wireless data networks, IEEE project 802 provides the standards for mass markets. With ever-growing usage, the demand for ubiquitous wireless networks increases. However, the achievable data rates decrease with the increasing distance of client devices from the infrastructure, and a sufficiently dense deployment of infrastructure devices is required to fulfill the customers' demand for broadband access. Today, these infrastructure devices rely on a wired backbone for background services; however, to reduce their costly deployment, they should interconnect wirelessly. In this case, devices mutually serve as wireless relays that forward and route packets over multiple wireless hops, and wireless mesh networks come into existence. In this article we provide an overview of wireless mesh networking and provide insights into the related standardization efforts in IEEE 802. For a more in-depth analysis, we focus on the draft WLAN mesh standard IEEE 802.11s and identify challenges for medium access control in multihop communication. Derived from our proposal to 802.1 Is, the current draft incorporates an optional medium access scheme that circumvents a performance gap. By means of simulations, we compare the performance of both solutions and provide an outlook for future 802 wireless systems that will be more reliable.     

Throughput analysis of IEEE 802.15.4 network under IEEE 802.11 network interference

This paper evaluates throughput of IEEE 802.15.4 network under the interference of a saturated IEEE 802.11 network using an analytic method. Packet losses due to both collisions among IEEE 802.15.4 and mutual interference between IEEE 802.15.4 and 802.11 are considered for throughput analysis. To include the interference from IEEE 802.11, we modified the state transition probabilities of IEEE 802.15.4 two-state Markov process model. Simulation results closely match the theoretical expressions confirming the effectiveness of the proposed model.     

IEEE802.11i无线局域网安全技术

介绍了当前无线局域网中的安全缺陷，分析了常见的无线局域网攻击手段，并在研究无线局域早期802．11标准安全缺陷的基础上重点分析了IEEE802．11i标准中的安全机制和关键技术。     

IEEE802.11g研究综述

全面介绍了IEEE802.11g标准的WLAN，详细讲述了IEEE802.11g草案标准的概念、特点、构件及体系结构、发展前景等，并探讨了实现IEEE802.11g WLAN所需的几项关键技术，同时分析了IEEE802.11g标准的网络性能。其关键技术包括直序列扩频调制技术及补码键控技术，包二进制卷积，正交频分复用技术等。有关IEEE802.11g的兼容性，同频共存性，自身的OFDM问题分析将成为研究的热点。     

An implementation of IEEE 1588 protocol for IEEE 802.11 WLAN

Wireless Networks - Clock synchronization is one of the enabling technologies for Wireless Local Area Networks (WLAN). It is crucial to perform applications such as data fusion, location detection...     

Enhancement of QoS differentiation over IEEE 802.11 WLAN

IQD, a distributed coordination function (DCF) with integrated quality of service (QoS) differentiation, is proposed in this letter to enhance QoS over IEEE 802.11 WLAN. DCF does not support any QoS differentiation. Enhanced DCF (EDCF) only supports delay differentiation. IQD can achieve both delay and packet-loss-rate differentiation by differentiating the initial window size and the retry limit. Simulation results show that IQD performs better than DCF and EDCF in enhancing QoS, and the proposed analytical model is valid.     

无线局域网标准 IEEE802.11g的技术优势

本文详细介绍了无线局域网标准IEEE802.11g的发展历程及其技术优势。     

Evaluation of IEEE 802.11 coexistence in WLAN deployments

Wi-Fi has become a successful technology since the publication of its first WLAN standard due to continuous advances and updates while remaining always backwards compatible. Backwards compatibility among subsequent standards is an important feature in order to take advantage of previous equipment when publishing a new amendment. At present, IEEE 802.11b support is still mandatory to obtain the Wi-Fi certification. However, there are several harmful effects of allowing old legacy IEEE 802.11b transmissions in modern WLAN deployments. Lower throughput per device is obtained at slow rates, but also the effect known as performance anomaly, which nearly leads to starvation of fast stations, has to be taken into account. Finally, backwards compatibility mechanisms pose an important penalty in throughput performance for newer specifications. This paper presents a thorough analysis of the current state of IEEE 802.11, comparing coverage range and throughput performance among subsequent amendments, and focusing on the drawbacks and benefits of including protection mechanisms.

     

无线局域网IEEE802.11n标准分析

802.11n是制定中的最新的无线局域网标准.首先介绍了无线局域网以及802.11标准系列的发展历史.然后介绍了802.11n标准的特点和发展现状.通过对WWiSE和TGnSynch两大技术阵营的对比.对802.11n的核心技术进行了分析介绍.最后对未来的802.11n标准做出了预测.