Date of Award
2025
Degree Type
Thesis
Degree Name
Master of Science in Ocean Engineering
Specialization
Acoustics
Department
Ocean Engineering
First Advisor
Lora J. Van Uffelen
Abstract
Electromagnetic signals, such as those used by Global Navigation Satellite Systems (GNSS), attenuate dramatically underwater, but acoustic signals can travel hundreds of kilometers, and can be used for positioning in much the same way. Concepts from GNSS can be applied to the subsurface context, as at a basic level, the principles of geo-positioning are identical. Key challenges in translating satellite positioning models to the underwater acoustic domain include differences in signal type as well as instrumentation and propagation environment. Acoustic signals travel at much slower speeds and are subject to significant environmental variability due to complex ocean dynamics. Here, the uncertainty of an acoustic positioning model utilizing glider type autonomous underwater vehicles as long-range receivers is reduced by leveraging vehicle data as a constraint. By using vehicle-derived measurements of horizontal speed along with headings, physical limitations are imposed on the positioning model, thus combining long- range acoustic reception data with vehicle data to increase the validity of position estimates. Additionally, horizontal dilution precision (HDOP) is applied to the context of subsurface arrays to inform error evaluation, ideal deployment locations for subsurface platforms, and array design. This approach strengthens the analogy between GNSS and underwater acoustic positioning, applying familiar concepts in a complex environment.
Recommended Citation
Salazar, Isaac B., "TOWARD PRECISE LONG-RANGE UNDERWATER ACOUSTIC GEO-POSITIONING: UTILIZING VEHICLE DATA AND DEEPENING THE GNSS ANALOGY THROUGH UNCERTAINTY MODELING" (2025). Open Access Master's Theses. Paper 2657.
https://digitalcommons.uri.edu/theses/2657