无线传感器网络时间同步协议动态切换机制

针对当前无线传感器网络时间同步协议通用性差的问题,提出了基于主动编程思想的时间同步协议动态切换机制,设计了能够动态适配的时间同步协议切换框架,重点讨论了节点间相互通信、时间戳标记、协议切换、本地时间与全局时间的转换等4个关键问题,并且在TinyOS（Tiny Operating System,微操作系统）平台上对新机制进行了仿真验证,比较了新机制同2种主流时间同步协议之间的性能差异.仿真结果表明：新机制能实现时间同步协议的动态配置,提高协同效率,节省切换开销,具有良好的应用前景.

A Dynamic Switching Mechanism for Time Synchronization Protocols in Wireless Sensor Networks

Based on the concept of active programming, a dynamic switching mechanism for time synchronization protocols is presented to make up for the poor versatility of current time-synchronization protocols for wireless sensor networks. A dynamically adaptive time synchronization protocol switching architecture is designed. Four key issues are discussed, communication among sensor nodes, timestamp mark, protocol switching and transformation between local time and global time. The new mechanism is verified through simulation on TinyOS （Tiny Operating System） and comparison of performance is made between the new mechanism and two types of mainstream protocols. The results show that the new mechanism is capable of dynamic configuration of time synchronization proto- cols. At the same time, it increases collaborative efficiency and saves switching overhead. Therefore, it has a good prospect for applications.