A wave propagation method in local angle domain
局部角度域波传播步进算法研究

A phase-space(local angle domain) marching algorithm of wave propagation is proposed in the general frame case,based on the wave equation for inhomogeneous media.The approach presents more freedom when choosing frame or orthogonal basis of one-way wave marching algorithm.Employing the Gabor-Daubechies tight frame which does not vary with frequency and depth but has the characteristic of scale-variability,the specific expression of one-way wave propagator and corresponding marching algorithm of wave field are derived.The high-frequency asymptotic expansion of the propagator based on Gabor-Daubechies tight frame is discussed in detail.Consequently the approximate analytic representation of the propagator in the situation of high-frequency and a small step size is obtained and its validity conditions are provided.The results of wave propagation using the accurate propagator and the high-frequency asymptotic one are compared for several heterogeneous models,which demonstrate that the wave fields are almost the same in certain conditions.