WLANs中基于最优竞争窗口的分布式自适应接入机制关键技术研究

分析WLANs中节点个数和QoS服务质量需求对网络性能的影响，研究饱和状态下分布式自适应接入控制机制中的关键技术与理论。通过研究信道状态反馈信息测量方法、网络基本信息估计算法和数据帧长度分布规律，本项目提出基于最优竞争窗口的分布式自适应接入控制机制及其性能分析方法。针对DCF/EDCA优化机制，通过在数据分析中约束同一节点成功传输的次数，本项目提出支持QoS服务质量需求的空闲时隙间隔测量方法，并提出基于当前数值的网络基本信息增量多门限估计算法。新方案保持较低的网络碰撞概率，结合数据交互模式，本项目进一步研究适应网络动态变化过程的数据帧长度分布规律。基于最优竞争窗口的分布式自适应接入机制为无线接入控制技术提供新的发展方向和研究思路。通过新方案的研究，获得具有自主知识产权的关键技术和接入协议，相关研究内容可以拓展到其它研究领域，为下一代无线通信提供理论技术支撑。

By studying the network performance in WLANs with different variations of node number and QoS requirements, we analyze the key technologies and theoretic approaches of distributed and adaptive access mechanisms in saturation status. We mainly analyze the feedback signals of channel status, the estimation algorithm of network base information and the length distribution of data frames, and then propose the distributed and adaptive access mechanism based on the optimal contention window with the analysis method of network performance. Aiming at the optimized access mechanisms of DCF/EDCA, we propose a measurement of idle slot intervals supported QoS requirements and a delta estimation algorithm of basic information of network with multiple thresholds based on the current values by constraining the number of successful transmissions of the same node. By combining with the interactive models of data frames, we further analyze the length distributions of data frames which are adapted to the dynamic process of network scale due to the low collision probability of network with the new mechanism. The proposed access mechanism creates a new way and method to analyze the network performance of wireless access mechanism.