SPATIAL COHERENCE OF ULTRASONIC SPECKLE IN COMPOSITES

被引：18

作者：

DERODE, A

FINK, M

机构：

[1] Laboratoire Ondes et Acoustique, Université Paris VII-ESPCI, 75231, Paris Cedex 05

来源：

IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL | 1993年 / 40卷 / 06期

关键词：

D O I：

10.1109/58.248209

中图分类号：

O42 [声学];

学科分类号：

070206 ; 082403 ;

摘要：

Pulsed echography in a scattering medium generates speckle noise. Its random nature implies a statistical processing of the backscattered signal. The second-order statistics (i.e., autocorrelation) can provide information about the structure of the medium and help detect a possible defect. The spatial autocorrelation function is related to the spatial coherence of the backscattered waves, which determines the speckle noise level. Specifically this spatial coherence approach is applied to anisotropic fiber-reinforced composites. We present theoretical as well as experimental results, and we show how the autocorrelation function changes with the orientation of the layers inside the composite, thus pointing out its anisotropy.

引用

页码：666 / 675

页数：10