摘要
声相关计程仪首先利用加权最小二乘法确定目标函数,然后通过序列二次规划法估计速度。考虑海底混响数据时空相关函数宽度的减小、相关系数点与相关函数中心点间距的增大,都会导致相关系数的均值减小、分布范围增大,此时相关系数在目标函数中对应项的权重也应当减小。在这样的前提下,引入调节参数μ,调节权重函数的宽度,使设备在各个速度下测速相对偏差的一致性达到最优,提高速度估计精确度。调节参数在设备标定与验证试验中确定,不同的设备可能具有不同的调节参数。试验数据证明了该方法对不同声相关计程仪测速精确度的提高都有效果。
An acoustic correlation log utilizes the weighted least square method to determine objective function and the sequential quadratic programming to estimate velocity. The calculation of weights is modified by considering the characteristics of the spatial-temporal correlation of bottom echo. The correlation function and the weight function all have the bell-shaped form. Along with the decrease of the correlation function width or the increase of the distance of the correlation point away from the peak, the mean value of correlation coefficient decreases and its distribution in- creases, then the weight of the corresponding term of the correlation coefficient in the objective function should also decrease. Under this circumstance, a parameter μ, which can adjust the width of the weight function, is introduced to enhance the consistency and the accuracy of velocity estimation. The adjustment parameter μ is determined in the calibration of an acoustic correlation log, and different devices may have different adjustment parameters. Trial data has proved the effectiveness of this method in improving the velocity measurement accuracy of different acoustic correlation logs.
作者
闫善勇
赵二亮
邱薇
王长红
YAN Shan-yong;ZHAO Er-liang;QIU Wei;WANG Chang-hong(Ocean Acoustic Technology Center, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China;University of Chinese Academy of Sciences, Beijing 100049, China;Beijing Engineering Technology Research Center of Ocean Acoustic Equipment, Beijing 100190, China)
出处
《声学技术》
CSCD
北大核心
2019年第5期502-507,共6页
Technical Acoustics
关键词
声相关计程仪
加权最小二乘
序列二次规划
测速精确度
acoustic correlation log
weighted least square
sequential quadratic programming
accuracy of velocity measurement
