27 research outputs found
Ray-based description of normal mode amplitudes in a range-dependent waveguide
An analogue of the geometrical optics for description of the modal structure
of a wave field in a range-dependent waveguide is considered. In the scope of
this approach the mode amplitude is expressed through solutions of the ray
equations. This analytical description accounts for mode coupling and remains
valid in a nonadiabatic environment. It has been used to investigate the
applicability condition of the adiabatic approximation. An applicability
criterion is formulated as a restriction on variations of the action variable
of the ray.Comment: 11 pages, 5 figure