Cramér-Rao bounds of source localization with distributed sensors in underwater multipath environment

In this paper, the Cramér-Rao lower bounds (CRLB) and the maximum likelihood estimator (MLE) are derived for estimating the underwater source location. An underwater source, four distributed underwater receivers with known location and time synchronization between source and receivers are assumed. If the reflecting geometry is known and the multipath is detectable and resolvable, it is shown that with exploiting the multipath information, the accuracy of source location estimation can be improved. Numerical examples are presented to illustrate the behavior of these bounds.