PAGE CONTENTS
Objectives
The aim of this programme is to investigate the feasibility of high data rate communications from satellite to autonomous underwater vehicles (AUVs) via laser communication. This requirement is in response to the increasing number of AUV and underwater devices being deployed and the requirement for greater capacity information transfer underwater.
Currently available underwater communications via acoustic and RF technologies are suited to long range, low data rate and short-range, high data rate respectively. Additionally, both acoustic and RF technologies do not offer communication channels through the air-water interface. By exploring the opportunities offered by optical communications technology there is potential for long range, high data rate communications through the air-water interface, exploiting to the relatively low attenuation of blue-green light through both the atmosphere and water.
Challenges
The key challenge of the project is overcoming the technical challenges posed by the environment through which the optical link must pass. Water is a highly scattering medium that cannot be avoided in this scenario, a significant amount of signal loss and dispersion will occur through water and must be overcome.
Challenges are also posed by the size, weight and power constraints that will be imposed on a system due to the constraints of both AUVs and satellites.
System Architecture
The project outcome is a technology readiness level 2 (TRL2) baseline technical solution for achieving space to underwater communications using laser communications. This solution will include the following:
-
Combined impact of the underwater and atmospheric channel behaviours,
-
Technologies including lasers and detectors,
-
Link budget, aperture sizes and power levels,
-
System scenarios and,
-
Waveform and modulation formats.
Recommendations for future development of the solution will be generated based on the identified limitations with the aim to process the technology to higher TRL in the future.
Plan
The feasibility study runs between March 2025 and November 2025, during which four main technical areas will be explored:
-
Identification AUV use cases and review of current communication methods,
-
Generation of technical requirements for space to underwater communications
-
Feasibility study and trade off analysis of potential technical solutions
-
Evaluation of identified technical solutions
Two key milestones will occur during the feasibility study, the first is scheduled for June 2025 and will occur when technical areas 1 and 2 of the feasibility study are complete. The second milestone will occur upon the completion of the entire study.
Current Status
The project is progressing well with the team finalising the first of the four main technical areas. Four uses cases for space to underwater communications on AUVs and the scenarios within which they would operate have been identified, these are:
-
Long Range Oceanographic Surveys,
-
Subsea Infrastructure Monitoring,
-
Mine Counter Measures and,
-
Maritime Search and Rescue Operations.
Additionally, a review of current communication methods employed by AUVs, and state of the art communication technologies has been conducted. Next steps include establishing a set of technical requirements and exploring their feasibility.
Companies
