An increasing number of aircraft, vehicles and ships share transport spaces. This requires a high degree of coordination. Coordination may be achieved centrally, which is the mode chosen for railways, or may be rule-based, as implemented in road traffic. In aeronautics and maritime transport, electronic navigation aids and radio communications already play a major role today. In the context of growing traffic and further automation, such aids will be increasingly required in other areas as well. Today’s electronic systems are, above all, designed to support pilots and captains. Communications takes place via voice-based systems, for example. Current systems often make use of expensive infrastructures, and do not take full advantage of GPS and Galileo. As a consequence, the institute is working on navigation and communications technologies that provide the reliability and availability needed for supporting safety-of-life operations, while at the same time being independent of expensive infrastructures.
The institute sets standards in aeronautics
The elimination of a communication bottleneck caused by the increasing traffic as well as the improvement of all-weather flight capabilities are major challenges in aeronautics. They will be addressed while reducing costs at the same time.
The communication bottleneck is addressed by the L-Band Digital Aeronautical Communications System (LDACS). L-DACS re-uses frequencies already used by other systems without disturbing them. It creates a universal interface for data and voice communications. In addition, it is intended to also provide distance measurement and emergency positioning. The institute plays a leading role in the development of LDACS. Its standardization by the International Civil Aviation Organization (ICAO) has just started and is strongly supported by the institute.
The all-weather flight capability is limited most of all by the current instrument landing system. In the future, final approach and landing shall be supported by GPS and Galileo-based systems. The first steps in this direction have already been taken: thanks to the ionosphere modelling carried out by the institute, the first CAT I system outside the United States could be made operational in Bremen. It allows an aircraft to land when the pilot sees the landing strip after a guided descent to 200 feet. The goal of the institute is to develop future systems that allow completely blind landings. First tests of such systems were carried out successfully by the institute at the Brunswick Airport, Germany.
Maritime safety as a new area of application
Shipping is another area where all-weather capabilities are of crucial importance. The increasing number of ever larger vessels, which need to maneuver in harbors and narrow fairways, poses a big challenge. In contrast to aeronautics, massive reflections of signals from the ships’ hulls and from the environment make positioning difficult. In some situations it becomes impossible to estimate positions using satellite signals alone. Captains and pilots do, however, require a reliable source of information about their position and their surroundings. The institute is working on methods that involve other sensors to improve accuracy and to detect and compensate potential sources of error. The results are an important contribution to the standardization by the International Maritime Organisation (IMO). Vessel positions are currently shared with nearby ships using the so-called Automatic Identification System (AIS), but they are not necessarily trustworthy. For this reason, methods developed by the institute compare positions provided by AIS with own radar measurements. In this way, even ships that are not equipped with AIS as well as other obstacles can be located, integrated into maps, and even shared with other ships. In collaboration with partners, including the US Coast Guard, the institute is developing a standard for communications between ships, with the coast, and also involving satellites.
Railway Collision Avoidance System
Trains move along one-dimensional tracks. On main routes, expensive infrastructures ensure collision-free railway traffic. On secondary lines, this is not the case, and sadly collisions still happen once in a while. The institute has therefore developed the socalled ‘Railway Collision Avoidance System’ (RCAS), which uses satellite positioning and radio communications to detect dangerous situations without requiring costly infrastructure. This system was industrialized and is sold by the institute´s spin-off ‘Intelligence on Wheels’. The Harz Narrow-Gauge Railway is the first to be equipped with this system.