基于稳健回归的TTE时钟补偿算法

时间触发以太网(time-triggered ethernet, TTE)通过精确的时间调度,保证了通信数据的实时性传输,满足了航空电子、运输及工业自动化等众多领域中关键安全系统的传输要求。然而,现有的TTE标准虽然规定了时间触发以太网的时钟同步流程,但未对时钟补偿问题给予具体解决方法。针对TTE的时钟同步特点,提出了一种基于稳健回归的时钟同步补偿方法。通过稳健回归算法对时钟误差进行估计,再根据估计误差对各节点的本地时钟进行补偿,所提出的算法成功解决了传统时钟补偿方法导致的时钟跳变和野值影响的问题。仿真结果也证实了,在野值比例不大于50%的情况下,所提算法在时钟同步精度方面明显优于传统的直接补偿算法和无稳健性的最小二乘补偿算法。

Clock compensation scheme based on robust regression in TTE

Via accurate time scheduling, time-triggered ethernet (TTE) ensures real time data communication and satisfies the transmission requirements of some critical safety systems in the fields of avionics technology, transportation, industrial automation and so on. However, existing standards just discuss the clock synchronization procedure and does not give a solution to the clock compensation problem. Considering the feature of clock synchronization in TTE, a clock compensation algorithm based on the robust regression method is proposed. The proposed algorithm robustly evaluates the clock skews of local clocks and compensates it, which eliminates the clock jump problem of traditional direct compensation and impacts from outliers in the network. The simulation results show that clock synchronization precision of the algorithm in this paper outperforms direct compensation and non-robust least square compensation as long as the ratio of outliers in the network is no more than 50%.