THE LARGER PERTURBATION INVERSION METHOD OF 2-D MEDIUM PARAMETERS

✍ Scribed by X.-R. Ma; Y.-Q. Niu; J. Dai; W.-H. Huang

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 156 KB
• Volume: 206
• Category: Article
• ISSN: 0022-460X
• DOI: 10.1006/jsvi.1997.1082

✦ Synopsis

The problem of parameter inversion in an inhomogeneous medium was studied and a generalized ray approximation method to inverse the 2-D medium parameters is introduced in this paper. By using referential and perturbational variables, the medium parameters of the wave equation have been rewritten. By using the Green function theory, the integral equation of perturbational parameters was obtained. Based on the local principles of wave function and ray theory in inhomogeneous medium, a generalized ray approximation form of the total wave field is introduced. By defining the medium parameters function, attention has been focused on the Fredholm integral equation of the first kind. By using convolution transforms, the solution of the medium parameters function in 2-D medium was obtained. The perturbations of medium parameters are usually not greater than 20% in the Born weak scattering method. However, in this paper the numerical results show that when the perturbations of the medium parameters are within 50%, this method can effectively inverse its variation.