Pascal Jean-Claude, Thomas Jean-Hugh, Li Jing-Fang
Laboratoire dAcoustique de lUniversite du Maine (CNRS UMR 6613) and Ecole Nationale Superieure dIngenieurs du Mans (ENSIM), Universite du Maine, rue Aristote, 72085 Le Mans Cedex, France.
J Acoust Soc Am. 2008 Oct;124(4):2085-9. doi: 10.1121/1.2973232.
It was recently shown that the statistical errors of the measurement in the acoustic energy density by the two microphone method in waveguide have little variation when the losses of coherence between microphones increase. To explain these intervals of uncertainty, the variance of the measurement is expressed in this paper as a function of the various energy quantities of the acoustic fields--energy densities and sound intensities. The necessary conditions to reach the lower bound are clarified. The results obtained are illustrated by an example of a one-dimensional partially coherent field, which allows one to specify the relationship between the coherence functions of the pressure and particle velocity and those of the two microphone signals.
最近研究表明，当传声器之间的相干损耗增加时，波导中双传声器法测量声能密度的统计误差变化很小。为了解释这些不确定区间，本文将测量方差表示为声场各种能量量（能量密度和声强）的函数。阐明了达到下限的必要条件。通过一维部分相干场的例子说明了所得结果，这使得人们能够确定压力和粒子速度的相干函数与两个传声器信号的相干函数之间的关系。
