Chen Yi, Zheng Xiaoqing, Luo Yaozhi, Shen Yanbin, Xue Yu, Fu Wenwei
College of Civil and Architecture Engineering, Zhejiang University, Hangzhou 310058, China.
Center for Balance Architecture, Zhejiang University, Hangzhou 310058, China.
Sensors (Basel). 2022 Jun 24;22(13):4784. doi: 10.3390/s22134784.
Wireless sensor networks usually suffer from the issue of time synchronization discrepancy due to environmental effects or clock management collapse. This will result in time delays between the dynamic responses collected by wireless sensors. If non-synchronized dynamic response data are directly used for structural modal identification, it leads to the misestimation of modal parameters. To overcome the non-synchronization issue, this study proposes a time synchronization approach to detect and correct asynchronous dynamic responses based on frequency domain decomposition (FDD) with frequency-squeezing processing (FSP). By imposing the expected relationship between modal phase angles extracted from the first-order singular value spectrum, the time lags between different sensors can be estimated, and synchronization can be achieved. The effectiveness of the proposed approach is fully demonstrated by numerical and experimental studies, as well as field measurement of a large-span spatial structure. The results verify that the proposed approach is effective for the time synchronization of wireless accelerometer sensors.
由于环境影响或时钟管理崩溃，无线传感器网络通常会面临时间同步差异问题。这将导致无线传感器收集的动态响应之间出现时间延迟。如果将未同步的动态响应数据直接用于结构模态识别，会导致模态参数的错误估计。为了克服非同步问题，本研究提出了一种时间同步方法，基于具有频率压缩处理（FSP）的频域分解（FDD）来检测和校正异步动态响应。通过施加从一阶奇异值谱中提取的模态相位角之间的预期关系，可以估计不同传感器之间的时间滞后，并实现同步。数值和实验研究以及大跨空间结构的现场测量充分证明了所提方法的有效性。结果验证了所提方法对无线加速度计传感器的时间同步是有效的。
