Aymé-Bellegarda E J, Habashy T M
IBM T. J. Watson Research Center, Yorktown Heights, New York 10598.
J Acoust Soc Am. 1992 Jun;91(6):3104-15. doi: 10.1121/1.402871.
This work is concerned with the modeling of elastic wave scattering by solid or fluid-filled objects embedded in an inhomogeneous elastic background. The medium is probed by a monochromatic force and the scattered field is computed (forward problem) or observed (inverse problem) at some known receiver locations. Based on vector integral equations for elastic scattering, a general framework is developed, independent of both the problem geometry and the transmitter-receiver characteristics. This framework encompasses both forward and inverse modeling. In the forward model, a Born approximation for an inhomogeneous background is applied to obtain a closed form expression for the scattered field. In the inverse model, this approximation is also invoked to linearize for the multiparameter characteristic of the object. Finally, an iterative inversion scheme alternating forward and inverse modeling is proposed to improve the resolution and accuracy of the reconstruction algorithm.
这项工作关注的是嵌入非均匀弹性背景中的固体或流体填充物体对弹性波散射的建模。通过单色力探测该介质，并在一些已知的接收器位置计算散射场（正向问题）或观测散射场（反向问题）。基于弹性散射的矢量积分方程，开发了一个通用框架，该框架与问题几何形状和发射器 - 接收器特性均无关。此框架涵盖正向建模和反向建模。在正向模型中，应用非均匀背景的玻恩近似来获得散射场的闭式表达式。在反向模型中，也调用此近似对物体的多参数特性进行线性化。最后，提出一种交替进行正向和反向建模的迭代反演方案，以提高重建算法的分辨率和准确性。
