无线局域网络抗干扰多路访问机制的研究：跨层协议设计与原型系统实现

There are two channel access methods in the IEEE 802.11 deployed WLANs, including the contention-based DCF (Distributed Coordination Function) and the polling-based PCF (Point Coordination Function) method. Both methods have serious problems which can dramatically reduce the network throughput. This project aims to design a novel cross-layer interference resistance multiple access approach to combat the key problems of 802.11 standard's channel access methods and improve the throughput. Specifically, we will devise physical layer mechanisms to resist the interferences introduced by the control frames, and design MAC layer mechanisms to increase concurrent data transmissions while avoid their collisions. The proposed cross-layer protocol is an integrated solution geared to both DCF and PCF channel access methods to improve the throughput of wireless networks. We will conduct a series of hardware experiments to validate the feasibility of the physical layer mechanisms. We will also conduct completed simulations to measure the effectiveness of the cross-layer protocol design. Based on the experiment and simulation results, we will be able to configure the proper parameters for the system to achieve the optimal performance. The proposed approach is designed to be compatible with current WLAN standards and can be incorporated into WLAN protocols and products seamlessly. Moreover, we propose to implement a prototype for the proposed scheme so as to verify its potentials in deploying in large-scale networks. The platform designed in this project, including both simulations and hardware experiments, can also facilitate further research in related fields and provide useful guidance for the design of real systems. All these outcomes will make important contributions to the improvement of the overall performance of future WLANs.

随着移动设备的大规模部署，无线网络带宽日益不足，提升网络传输性能的需求日益迫切，而现有方案却有诸多不足，无法满足当前的需求。本项目针对无线局域网广泛采用的IEEE 802.11协议定义的两种通道接入方式进行研究，分析影响传输性能的多个关键问题和改进机会点，设计物理层与MAC层相结合的基于抗干扰多路访问机制的跨层传输协议，提升无线网络整体传输性能。本项目提出一套完整的协议体系同时面向两种通道接入方式进行性能提升改进，构建无线网络的实验平台和仿真系统，以验证物理层方案的正确性和跨层协议的有效性，分析所设计协议在各种条件下的性能指标，合理配置系统参数，优化系统性能。本项目还将构建实验原型系统，验证方案在实际网络中支撑大规模部署的能力，为进一步研究提供实验依据及仿真平台，为实际系统设计提供指导。本项目的研究以既有标准与自主创新相结合，提出具备实际网络部署能力的方案，对提升无线网络性能具有重要意义。

随着移动设备的大规模部署，无线网络带宽日益不足，提升网络传输性能的需求日益迫切，而现有方案却有诸多不足，无法满足当前的需求。本项目针对无线局域网广泛采用的IEEE 802.11 协议定义的两种信道访问控制方法，即基于竞争的分布式协调功能和基于中心节点控制的点协调功能，进行研究，分析影响传输性能的多个关键问题，探寻改进网络传输性能的机会点，设计物理层与媒体接入控制层相结合的基于抗干扰多路访问机制的跨层传输协议，允许节点在有干扰的情况下并发传输，提升无线网络整体传输性能。本项目提出一套基于抗干扰多路访问机制的跨层传输协议的协议体系，面向两种通道接入方式进行性能提升改进，并结合软件定义网络的特性，设计优化接入机制和协议算法；本项目同时构建无线网络的实验平台和仿真系统，以验证物理层方案的正确性和跨层协议的有效性，分析所设计协议在各种条件下的性能指标，合理配置系统参数，优化系统性能指标。本项目构建实验硬件原型系统，验证方案在实际网络中的部署能力，为进一步研究提供实验依据及仿真平台，为实际系统设计提供指导。本项目以既有标准与自主创新相结合，提出具备实际网络部署能力的方案，其研究成果已经在国际顶级杂志和会议上发表了多篇文章，并对相关技术申请了国家专利。本项目所提出的方案对提升无线网络性能具有重要意义。