摘要
针对无线通信网络中各通信节点间守时存在较大的误差,提出了一种基于传感器网络时间同步协议TPSN双向时间同步算法,设计了一种小型化、模块化的高精度时统系统,可用于跳频同步和TDMA组网体制下的时隙同步。首先选取主机,仅当10 s内未收到校时呼叫的节点设置为主机;其次发送及应答,规定主机1 s内仅对一个从机请求作出应答;最后通过记录校时主从节点的发送时刻,扣除或补偿逻辑处理延迟、射频传输延迟、校时两端的频差等,计算节点间的同步误差。在不同条件下进行了仿真实验,节点间的同步误差可以精确到30 ns左右,表明该方案时间同步精度高、误差较小,可满足该无线通信网络中各节点间协同探测、协同攻击和协同干扰等战术目标的需要。
Aiming at the large error of keeping time between communication nodes in wireless communication networks, we propose a two-way time synchronization algorithm based on timing-sync protocol for sensor network(TPSN). We design a miniaturized and modular high-precision time synchronization system which can be used in frequency hopping synchronization and time slot synchronization under the TDMA network architecture. Firstly, we set the node which has not received any call within 10 seconds as the host. Secondly, the host responds to only one slave within 1 second. Finally, the synchronization error between nodes is calculated by recording the sending time of master-slave node, deducting or compensating the logic processing delay, RF transmission delay, and the frequency difference between the two ends of the calibration. Simulations under different conditions show that the synchronization error between nodes can be as accurate as about 30 nanoseconds. This indicates that the solution's time synchronization accuracy is high, and the error is small, thus it can meet the needs of tactical objectives such as collaborative detection, collaborative attacks and collaborative jamming between nodes in the wireless communication network.
引文
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