Harrison Chris H
Emeritus Scientist, Centre for Maritime Research and Experimentation, Viale San Bartolomeo 400, 19126 La Spezia, Italy.
J Acoust Soc Am. 2017 Apr;141(4):2812. doi: 10.1121/1.4981120.
The cross-spectral density of ocean ambient noise is usually estimated from the product of the complex hydrophone signals, each of which already corresponds to the summed responses of sources from all angles. The true coherence is the integral over all angles of the angle-dependent product. The influence of this distinction on necessary time integration in geoacoustic inversion and passive fathometry is explored, and a meaningful separation of the cross-spectral density matrix into Toeplitz and Hankel parts is proposed. Various processing techniques are applied to synthesized data and some experimental vertical array data in a passive fathometry context. Passive fathometry is only sensitive to the Hankel part of the matrix.
海洋环境噪声的互谱密度通常由复水听器信号的乘积估计得出，其中每个复水听器信号已对应于来自所有角度的源的总和响应。真实相干性是角度相关乘积在所有角度上的积分。探讨了这种差异对地质声学反演和被动测深中必要时间积分的影响，并提出了将互谱密度矩阵有意义地分离为托普利兹部分和汉克尔部分的方法。在被动测深的背景下，将各种处理技术应用于合成数据和一些实验垂直阵列数据。被动测深仅对矩阵的汉克尔部分敏感。
