title: Effect of dispersion on the convergence rate for Green's function retrieval.
abstract: Much information about wave propagation in a variety of structures has been obtained from Green's function retrieval by noise correlation. Here it is examined how dispersion affects Green's function retrieval and, in particular, its signal-to-noise ratio (SNR). On recalling how the inherent spread of a signal due to band limitation is augmented by spread due to dispersion and propagation distance, and how both affect amplitude, it is argued that SNR in highly dispersive media can be substantially lowered by strong dispersion. It is argued that this is most relevant for gravity waves over large propagation distances in the ocean or atmosphere. In particular, it is discussed that dispersion could explain recent retrieval failure from surface gravity wave noise in the ocean. Methods are considered to ameliorate the poor SNR due to dispersion. Numerical simulation is used to substantiate the analytic results.
authors.affiliation: Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801, USA.
authors.forename: John Y
authors.initials: JY
authors.lastname: Yoritomo
authors.affiliation: Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801, USA.
authors.forename: Richard L
authors.initials: RL
authors.lastname: Weaver