Necessary and Sufficient Observability Conditions for Bearings-Only Target Motion Analysis

摘要

The observability requirements for bearings-only target motion analysis (TMA) are rigorously established by solving a third-order nonlinear differential equation. Closed-form expressions are developed and subsequently used to specify necessary and sufficient conditions on own ship motion that ensure a unique tracking solution. It is shown that for certain types of maneuvers the estimation process remains unobservable, even when the associated bearing rate in non-zero. Such maneuvers are frequently overlooked in heuristic discussions of TMA observability, which may account for some common misconceptions regarding the characteristics of accepatable own ship motion.