Underwater Optical Wireless Localization

Abstract

With the development of underwater technology, a more significant number of scholars and scientists have begun to pay attention to the development and application of UWOC (Underwater optical wireless communication) and UWONs (Underwater optical wireless networks). These studies require underwater localization technology to provide accurate location information. This thesis applies existing underwater positioning technology with knowledge of the LED Lambertian pattern with the aim of developing a low latency underwater positioning concept that helps locate the fast-moving underwater targets.

A key contribution of this thesis is the development of an adaptive time slot (ATS) approach. Each buoy transmits signals in disjoint time slots which repeats periodically. Given the random locations and orientations of the buoys, the distance from each buoy to the target will not be identical and will change in time. These changes in position lead to overlap, discontinuity or loss of signals transmitted from buoys in each time slot. The ATS approach uses the structure of these distortions received from multiple buoys to improve positioning accuracy. The thesis provides comparison results with and without ATS in several practical scenarios.