基于信标同步及信道预测的井下无线网络切换机制研究

Handoff mechanism of underground mine wireless network based on beacon synchronization and channel estimation

矿井机车无人驾驶系统面临的一个主要问题是车载移动节点MN在机车轨旁AP间进行切换产生的通信延时问题。传统切换机制扫描所有信道,时延过大,难以满足系统通信的实时性要求。因此建立井下802.11无线网络模型,提出基于信标同步及信道预测的井下无线网络切换机制,该机制通过同步AP信标帧的广播时间和维护AP邻接链表的方法减少切换延时。通过仿真实验验证该机制能够将切换时延降到实时通信系统的要求,对比传统硬切换机制可降低切换时延达70%以上。

A major problem of achieving mine locomotive unmanned system is the communication delay caused by the MN in mine laneway moving from one access point to another one. The traditional handoff mechanism which has probed channels by full-scan method causes high handoff delay and can＇ t meet the requirement of real-time network traffic. So the model of underground mine wireless network is established and beacon synchronization and handoff mechanism of underground mine wireless network based on beacon synchronization and channel estimation is presented to reduce the channel staying time and the number of scanned channels with the way of beacon synchronization and neighbor list of APs. The simulation validates that the delay of the mechanism could be reduced to satisfy the requirement of real-time communication system and reduces at least 70% of the handoff delay than hard handoff mechanism.