Analysis of 3D Localization in Underwater Optical Wireless Networks with Uncertain Anchor Positions

TL;DR

This paper investigates 3D localization accuracy in underwater optical wireless sensor networks considering anchor position uncertainties, deriving a CRLB expression and validating it through numerical simulations.

Contribution

It provides a closed-form CRLB for 3D underwater localization with anchor uncertainty, incorporating ToA and AoA measurements, and compares different estimation methods.

Findings

CRLB derived for uncertain anchor positions

Numerical validation of analytical results

Comparison of localization methods (LSS, WLSS)

Abstract

Localization accuracy is of paramount importance for the proper operation of underwater optical wireless sensor networks (UOWSNs). However, underwater localization is prone to hostile environmental impediments such as drifts due to the surface and deep currents. These cause uncertainty in the deployed anchor node positions and pose daunting challenges to achieve accurate location estimations. Therefore, this paper analyzes the performance of three-dimensional (3D) localization for UOWSNs and derive a closed-form expression for the Cramer Rao lower bound (CRLB) by using time of arrival (ToA) and angle of arrival (AoA) measurements under the presence of uncertainty in anchor node positions. Numerical results validate the analytical findings by comparing the localization accuracy in scenarios with and without anchor nodes position uncertainty. Results are also compared with the linear least square (LSS) method and weighted LLS (WLSS) method.