Feasibility of passive oceanic acoustic tomography: a Cramer Rao bounds approach

This paper completes the proof of the feasibility of passive ocean acoustic tomography (OAT) by using the Cramer Rao bounds (CRB) tool. CRB are calculated on a shallow environment modeled by a homogeneous layer over a semi infinite sediment layer. The results are that considering relative delays instead of absolute delays degrades the estimation of ocean parameters. Taking into account the spatial structure (angles of arrival) enables one to improve performances of passive OAT and have similar performances as soon as accuracy of physical parameter estimations are conserved than active OAT for absolute delays only.