A new velocity estimation method using spectral identification of noise
A new velocity estimation method using spectral identification of noise
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DOI：
10.1016/j.flowmeasinst.2007.06.008
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发表时间：
2008-06-01
影响因子：
2.2
通讯作者：
Pallares, Anne
中科院分区：
文献类型：
--
作者：
Fischer, Stephane;Schmitt, Philippe;Pallares, Anne
在所有测量技术中，人们都追求准确性和精确度。在超声多普勒测速中，这些质量很大程度上取决于多普勒信号的信噪比以及速度估计器的性能。超声相干多普勒测速中应用最广泛的估计方法是脉冲对法。它的成功归功于该算法与无偏估计器相结合的计算效率。不幸的是，对于大范围的实验流体流动，脉冲对估计效率较低，特别是对于信噪比可能非常低的清水或浓缩泥浆，或者对于多普勒信号具有广谱的高度湍流。我们的方法基于多普勒频谱信息的处理。它使用受理论模型和实验观察启发的简单参数识别。它通过消除噪音和随后的切割来发挥作用。因此，我们开发了一种在精度方面优于脉冲对算法的快速速度估计算法。通过向实验多普勒信号添加不同级别的高斯白噪声来评估该方法的鲁棒性。结果表明，与脉冲对方法相比，抗噪能力提高了十倍。 (c) 2007 Elsevier Ltd. 保留所有权利。
In all measurement techniques one seeks accuracy and precision. In ultrasonic Doppler velocimetry, those qualities strongly depend on signal to noise ratio of the Doppler signal and on the performance of the velocity estimator. The most widely used estimation method in ultrasonic coherent Doppler velocimetry is the pulse pair method. Its success is due to the computation efficiency of the algorithm combined to an unbiased estimator. Unfortunately, for a wide range of experimental fluid flows, the pulse pair estimation is less efficient, especially for clear water or concentrated mud where the signal to noise ratio can be very low, or for highly turbulent flows where the Doppler signal has a broad spectrum. Our approach is based on the treatment of the Doppler spectral information. It uses a simple parametric identification inspired by theoretical models and experimental observations. It acts through noise subtraction and subsequent cutting. Thus, we have developed a fast velocity estimation algorithm superior to the pulse pair one in terms of accuracy. The robustness of the method was evaluated by adding different levels of white Gaussian noise to an experimental Doppler signal. The results demonstrate an increase of noise immunity up to one decade compared to the pulse pair method. (c) 2007 Elsevier Ltd. All rights reserved.