Eigenray identification for non-planar propagation

Identifying ray paths connecting a source and receiver at specific locations, or eigenrays, is a trivial exercise in the case of planar propagation since only the initial inclination angle and arrival range of the ray must be considered. However, in the case of propagation in three dimensions, the eigenray search becomes a non-trivial two parameter search. An iterative eigenray search method has been developed employing the auxiliary parameters used to solve the transport equation to efficiently obtain eigenrays connecting a source and receiver in three dimensions. An overview of the method will be presented along with applications to propagation in a simple model atmosphere and analysis of data obtained during the Humming Roadrunner experiment in the fall of 2012.