摘要
采用全球定位系统实时动态监测技术GPS-RTK(Real-Time Kinematic)和加速度计对天津富民桥进行现场动态变形监测试验。将RTK接收机的采样频率进行内部升级,由1 Hz调至20 Hz,并设计RTK和加速度计联合监测装置。为削弱RTK监测数据中的多路径误差和随机噪声影响,提出一种基于自相关函数的总体经验模态(EEMD)滤波和切比雪夫滤波相结合的混合型滤波器,称为AFEC(Autocorrelation Function based EEMD and Chebyshev)混合滤波,对RTK采集得到的数据进行滤波处理,识别出桥梁的动态位移,并与加速度数据求积分得到的位移序列进行对比,结果基本吻合,说明AFEC滤波器可以有效地削弱RTK监测数据中的多路径误差和随机噪声。
The real-time dynamic monitoring technology of the global positioning system GPS-RTK(Real-Time Kinematic) and accelerometers were used to monitor the dynamic deformation of Fumin Bridge in Tianjin. The sampling frequency of the RTK receiver was internally upgraded from 1 Hz to 20 Hz. A joint monitoring device of RTK and an accelerometer was designed. In order to reduce the influence of multipath errors and random noise in RTK monitoring data, the AFEC hybrid filter(Autocorrelation Function based EEMD and Chebyshev) which was a combination of an autocorrelation function-based ensemble empirical mode decomposition(EEMD) filter and a Chebyshev filter was proposed. By filtering the data collected by RTK, the dynamic displacement of the bridge can be identified and compared with the displacement sequence obtained by integrating the acceleration data, and the results were basically consistent. It was shown that the AFEC filter can effectively weaken the multipath error and random noise in the RTK monitoring data.
引文
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