航空自组网拓扑透明时分多址接入协议设计与建模优化

Design and Modeling Optimization of Topology-transparent Time Division Multiple Access Protocol for Aeronautical Ad Hoc Network

航空自组网(AANET)允许节点通过单跳或多跳的方式直接通信,不需要依赖于地面控制中心,可为航空通信提供灵活的网络架构。针对该特点,设计一种改进的自组织时分多址接入(TDMA)协议。在保持时隙自组织选取和拓扑透明优势的基础上,引入时隙二次分配竞争策略,使网络节点能够竞争使用网络时帧中保持空闲和产生冲突的时隙。通过数学建模分析获得在二次分配阶段节点竞争预约时隙的最佳概率,实现时隙利用率的最优化。在EXata网络环境中的仿真实验结果表明,与现有自组织TDMA协议相比,该协议能提高网络时帧中时隙的利用率,获得更好的吞吐量性能。

Aeronautical Ad Hoc Network（ AANET） allows nodes to communicate through single hop or multi-hip way,and it does not need to rely on the ground control center. It provides flexible network architecture for aeronautical communication. Aiming at this characteristic,this paper proposes an Evolutionary Self-organizing Time Division Multiple Access（ ESTDMA） protocol for AANET. It aims to optimize the slot utilization of the existing STDMA protocol while preserving the advantages of it. By introducing a contention-based secondary slot allocation strategy,ESTDMA enables nodes to contend to utilize the free and collision slots in the frame. Meanwhile,an analytical model is developed to obtain the optimal contention probability for the nodes to contend for the slots. The accuracy of analytical model is validated through the comparison of the simulation results and the analytical results. Also,the simulation results in EXata network showthat the proposed protocol can effectively improve the slot utilization of the STDMA protocol,thus improving the performance dramatically.