Ms. Fokina et Vn. Fokin, Reflection of plane waves from an plastic layered medium: Resonance approach and numerical modeling, ACOUST PHYS, 46(5), 2000, pp. 605-612
The resonance formalism developed earlier by H. Uberall for st model of a l
iquid layer overlying a liquid halfspace is extended to a model of an elast
ic layer overlying an elastic halfspace. Using the Thomson-Haskell matrix t
echnique, an exact analytical expression is obtained for the complex reflec
tion coefficient. Characteristic equations are derived, and their roots, wh
ich determine the positions of the resonances of the reflection coefficient
for longitudinal and transverse waves, are obtained analytically. In the r
esonance approach, the exact expression for the reflection coefficient is r
eplaced by an approximate one that describes the behavior of the reflection
coefficient near the resonances. The comparison of the exact and approxima
te values of the reflection coefficient shows good agreement between the re
sults near the frequency and angular resonances. (C) 2000 MAIK "Nauka/Inter
periodica".