Contact localization and motion analysis in the ocean environment: A perspective

This paper presents a perspective on contact localization and motion analysis (CLMA) in the ocean environment. Such well-studied cases as passive hearings-only contact motion analysis, multipath ranging, and localization/tracking via arrays are used to illustrate the concept. The performance of current CLMA systems is shown to depend on the type and characteristics of the basic measurements developed by their time delay estimators, the acoustic channels linking contact and observer, and the type and description of relative motion between contact and observer. General classes of CLMA schemes are presented. Complexity is shown to depend on the linearity/nonlinearity of their solution equations, the degree to which a contact is observable at each sample time, and the relative motion between contact and observer. Contributions to total system gain, biasing issues, and candidate solutions are discussed. Comprehensive references are provided.