VDES R-Mode Performance Analysis and Experimental Results

Global Navigation Satellite Systems (GNSS) have become an essential part of maritime navigation, in particular to improve situational awareness and vessel traffic management. The dependence on GNSS creates vulnerability for maritime shipping. Driven by this vulnerability, the desire for a backup system for maritime navigation has been emerging. The VHF Data Exchange System (VDES) standard provides communication capabilities for maritime applications. VDES is currently being revised. As part of this revision, VDES will be extended by ranging and navigation functionalities, called R-Mode, as an alternative for maritime navigation. In this paper, we address system design aspects and evaluate the positioning performance of VDES R-Mode. We derive estimation theory bounds on the accuracy of VDES R-Mode distance and velocity. In a case study, we discuss and evaluate the benefit of satellite links to complement VDES R-Mode positioning. Furthermore, we introduce a Kalman filter for position and velocity tracking, which we apply to experimental data. We describe an experiment we conducted at Lake Ammer, southwest of Munich, and evaluate the VDES R-Mode positioning performance for this setup. Our experimental results show that VDES R-Mode is capable of achieving a 95th-percentile horizontal position error of 22?m. Thus, VDES R-Mode is a promising approach for a maritime backup system that can meet the IALA accuracy requirements

Conflicts Encountered with Bridge Team from the Perspective of Vessel Traffic Service Operators: A Research Within E-Navigation Concept

The hazards that threaten marine navigation safety in the intensive routes and critical straits need to be managed effectively. To manage these risks, the concept of e-navigation has been offered to all stakeholders of marine transportation. E-navigation basically aims to organize, serve, and exchange marine information systematically. It is considered that the relations between the stakeholders may constitute significant conflicts in exchanging marine information. The main purpose of this study is to reveal the sources of conflicts and risk scores on navigation operations encountered with the bridge team from the perspective of vessel traffic services operators (VTSOs). In order to determine the sources of the conflicts, the conflict-related literature has been thoroughly reviewed, a semi-structured interview form was developed, and the VTS supervisors have been interviewed. In discovering the sources of conflicts, content analysis has been carried out from the interviews. The findings have been discussed with the relevant experts, and risk scales have been developed to evaluate the risks of conflicts. The frequency of conflicts and the results have been evaluated by the VTSOs employed at the Center of VTS in İstanbul, and risk scores have been defined. The risk scores related to the conflicts indicated on the risk matrix and e-navigation designed solutions have been compared and discussed. The findings reveal that there are certain similarities between the high-scored risks regarding communication quality and reporting systems. Although e-navigation solutions focus on improving technical issues. Conflicts caused by interpersonal, cognitive, and personal features that are not covered by e-navigation solutions have an important place among the conflict sources

Integrated satellite-terrestrial connectivity for autonomous ships:Survey and future research directions

An autonomous vessel uses multiple different radio technologies such as satellites, mobile networks and dedicated narrowband systems, to connect to other ships, services, and the remote operations center (ROC). In-ship communication is mainly implemented with wired technologies but also wireless links can be used. In this survey paper, we provide a short overview of autonomous and remote-controlled systems. This paper reviews 5G-related standardization in the maritime domain, covering main use cases and both the role of autonomous ships and that of people onboard. We discuss the concept of a connectivity manager, an intelligent entity that manages complex set of technologies, integrating satellite and terrestrial technologies together, ensuring robust in-ship connections and ship-to-outside connections in any environment. This survey paper describes the architecture and functionalities of connectivity management required for an autonomous ship to be able to operate globally. As a specific case example, we have implemented a research environment consisting of ship simulators with connectivity components. Our simulation results on the effects of delays to collision avoidance confirm the role of reliable connectivity for safety. Finally, we outline future research directions for autonomous ship connectivity research, providing ideas for further work

Europe's Space capabilities for the benefit of the Arctic

In recent years, the Arctic region has acquired an increasing environmental, social, economic and strategic importance. The Arctic’s fragile environment is both a direct and key indicator of the climate change and requires specific mitigation and adaptation actions. The EU has a clear strategic interest in playing a key role and is actively responding to the impacts of climate change safeguarding the Arctic’s fragile ecosystem, ensuring a sustainable development, particularly in the European part of the Arctic. The European Commission’s Joint Research Centre has recently completed a study aimed at identifying the capabilities and relevant synergies across the four domains of the EU Space Programme: earth observation, satellite navigation, satellite communications, and space situational awareness (SSA). These synergies are expected to be key enablers of new services that will have a high societal impact in the region, which could be developed in a more cost-efficient and rapid manner. Similarly, synergies will also help exploit to its full extent operational services that are already deployed in the Arctic (e.g., the Copernicus emergency service or the Galileo Search and rescue service could greatly benefit from improved satellite communications connectivity in the region).JRC.E.2-Technology Innovation in Securit