Multiple Ray Tracing Within 3‐D Layered Media with the Shortest Path Method

Abstract

The purpose of this study is to introduce the multistage scheme incorporating with a modified shortestpath method (MSPM) for tracking multiple arrivals and simulating wavefront evolutions composed of any kind of combinations of transmissions, conversions and reflections in complex 3D layered media. The principle is first to divide the layered model into several different computational domains, and then to use the multistage technique to trace the multiple arrivals. It is possible to realize the multiple arrival tracking with the multistage technique because the multiple arrivals are the different combinations or conjugations of the simple incident, transmitted, reflected, and converted waves at the velocity boundaries (or discontinuities). Numerical tests and error analysis indicate that the multistage MSPM method retains the basic characteristics of the single‐stage MSPM approach, that is algorithm simplicity, numerical stability, high computational accuracy and speed, global solution and etc. Therefore it is a practical algorithm to track the multiple arrivals.

A Ray Tracing Tool for Propagation Modeling in Layered Media: A Case Study at the Chip Scale

“…Propagation in layered media has been often related to Extremely Low Frequency communications for subsurface and close-to-the-surface communications, geophysical prospecting and diagnostics [11], to radio-wave propagation for VHF/UHF links in environment where the layers represent ground, vegetation or snow-covered terrain and air [12]. Other fields of application include propagation in meta-materials, photonics crystals, solar cells and plasmonic devices [13], ultrasonic testing in geometrically complex structures like anisotropic, inhomogeneous materials [14], earthquake location in geophysics, migration imaging and travel time tomography [15].…”

“…According to a literature survey, propagation modelling in layered structures can be carried out according to some, different methodologies, spanning Sommerfeld integration methods [7], multipath formulations through the Green's functions representation [8], full numerical solutions [16] andmost of all -models based on either the Dyadic Green Function (DGF) [17]- [21] or Geometrical optics (Ray Tracing -RT) [2], [5], [14], [15], [22]. DGF is a physics based approach to propagation modelling aiming at the asymptotic evaluation of the overall received field, whereas RT addresses the different field contributions propagating along different optical paths that can be tracked between the transmitting and the receiving locations.…”