【摘要】 随着实时音频、视频等越来越多的新应用部署到无线网络上，针对应用特点，探索基于分布式的信道访问控制机制的无线网络QoS,对确保无线网络应用具有重要意义。传统EDCA机制是IEEE 802.11e协议在DCF机制基础上的服务质量支持扩展，但其静态参数无法适用于复杂多变的网络环境。为满足实际应用中的服务质量需求，对EDCA机制特点进行研究，分析基于参数集的发送机会、竞争窗口以及虚拟碰撞机制的优势和局限性，介绍具有代表性的相关研究成果，总结提高网络性能的改进算法，对未来EDCA机制的发展难点和研究方向进行展望。更多还原

【Abstract】 As more and more new applications such as real-time audio and video are deployed to wireless networks, exploring wireless network QoS based on distributed channel access control mechanism is of great significance to ensure wireless network applications according to the application characteristics. The traditional EDCA mechanism is an extension of IEEE 802.11e protocol based on DCF mechanism, but its static parameters cannot be applied to the complex and changeable network environment. In order to meet the QoS requirements in practical applications, this paper studied the characteristics of EDCA mechanism, analyzed the advantages and limitations of sending opportunities, competitive windows and virtual collision mechanism based on parameter sets, introduced representative related research results, summarized improved algorithms to improve network performance, and looked forward to the development difficulties and research directions of EDCA mechanism in the future.更多还原