超声波流量测量时差改进卡尔曼滤波

Modified Kalman filter of TDOA in ultrasonic flow measurement

在离散卡尔曼滤波器的基础上,针对超声波液压系统流量测量的时差信号的特征提出了离散卡尔曼滤波的改进方法,提高了普通卡尔曼滤波器对信号突变的识别跟踪能力。该方法采用切换函数来识别时差信号的突变,通过改变滤波器模型中系统噪声协方差阵实现了滤波器对时差信号突变的跟踪。实验结果表明,改进后的滤波器具有良好的消噪和瞬态响应能力。

Based on the scatter Kalman filter, a mending method of scatter Kalman filter is presented according to the character of TDOA signal to ultrasonic hydraulic system flow measurement. The infirmness recognizing and tacking ability of scatter Kalman filter to signal mutation is improved. The method applied the switching function to identify mutation of TDOA signal. The tacking of TDOA signal mutation is realized by changing the system covariance matrix of filter model. Experimental result is given to make sure the excellent eliminating noise and transient response ability of the mended filter.