A NOTE ON THE DERIVATION OF PARAXIAL EQUATION IN NONHOMOGENEOUS MEDIA

被引：2

作者：

HILLION, P

机构：

[1] Inst Henri Poincare-75231, Paris

来源：

SIAM JOURNAL ON APPLIED MATHEMATICS | 1992年 / 52卷 / 02期

关键词：

WAVE EQUATION; PARAXIAL APPROXIMATION; NONHOMOGENEOUS MEDIA; BICHARACTERISTICS; NULL GEODESICS;

D O I：

10.1137/0152018

中图分类号：

O29 [应用数学];

学科分类号：

070104 ;

摘要：

The paraxial approximation of the two-dimensional and three-dimensional wave equations in nonhomogeneous media is discussed. It is shown that the preferred direction of propagation is along the bicharacteristics of the wave equation. The paraxial equation is obtained by assuming that in this direction, the variation of the propagating wave is slow enough to make negligible its second derivative. The best way to get bicharacteristics is to consider them as the null geodesics of some Riemannian space.

引用

页码：337 / 346

页数：10