Lars Stenseng has been appointed professor in Satellite Geodesy at DTU Space from September 2021. (Photo: DTU Space/L. Stenseng)

New professor strengthens research in positioning systems

Information technology Satelittes
Lars Stenseng has been appointed professor in Satellite Geodesy at DTU Space. He will be working with precise and robust positioning utilizing Global Navigation Satellite Systems, GNSS.

New DTU Professor Lars Stenseng is an expert in Satellite Geodesy. He will be working at DTU Space with Global Navigation Satellite Systems, GNSS. These are satellite-based systems for navigation and positioning. They include the European Galileo, the US GPS and the Russian GLONASS. 

"My main task will be to build physical and data-driven infrastructure within GNSS that can support precise and robust positioning and navigation in real-time"
Lars Stenseng, newly appointed professor at DTU Space

GNSS plays an essential role in the green transition, supporting autonomy, including self-driving cars, drones, ships and robot systems, and route optimization to reduce energy consumption. If the signals from GNSS positioning systems can be processed and converted into useable data faster and more precisely, these systems can ensure much more efficient navigation.

"There has been a great deal of development within the GNSS area in recent years, including the realization of the European Galileo system and new methods for working with GNSS data, and I look forward to immersing myself in the area," says Lars Stenseng.

"My main task will be to build physical and data-driven infrastructure within GNSS that can support precise and robust positioning and navigation in real-time."

Strengthening DTU Space in the GNSS area

Lars comes from a professor position at Aalborg University, but he is not new to DTU. He took his PhD degree here in 2011, specializing in altimetry and GNSS systems. In 2019 he took up a position with the land surveyors at Aalborg University.

"We look forward to having Lars Stenseng on the team. He will be strengthening our efforts in the field of GNSS and satellite geodesy. Research and teaching in GNSS broadly support DTU's strategy within sustainability, digitalization, and delivering Europe's best engineering education. In addition, the field is a strategic priority for the Danish Agency for Data Supply and Efficiency (SDFE), our close partner on research-based consultancy," says Michael Schultz Rasmussen, head of the Division of Geodesy and Earth Observation at DTU Space.

Professor Stenseng will be working on several large GNSS projects.

One of them is the TAPAS project, a platform developed at DTU Space to test and develop systems for centimetre-precise positioning in, for example, urban environments based on satellite data. TAPAS consists of a network of reference stations covering Aarhus city and port. The system is available to companies and authorities that want to develop and test concepts for autonomous units. TAPAS is a collaboration between DTU Space, Aarhus Municipality, and SDFE that operates and owns the TAPAS platform.

Another project is DANGO that will support the Galileo High Accuracy Service by offering access to real-time transformations of coordinates between the inherent Galileo system and the Danish reference system to fit with positions in Danish maps and GIS data. This project is carried out in collaboration with the European Space Agency ESA and Aalborg University. GNSS infrastructure will be installed on three campuses at Danish universities. Among them DTU in Lyngby.

Potential for more efficient navigation in Greenland

The new DTU professor will also work with 'safety and security', which develops safe and reliable satellite navigation.

"For example, there may be systems that analyze GNSS data very fast, so that an aircraft preparing for landing can receive early warnings in case of incorrect GNSS positioning or system failure that again allows the pilot to switch to other navigation systems. This is something that often happens in Greenland, partly because the ionosphere near the North Pole is very active and can affect the signals coming down from the GNSS satellites," explains Lars Stenseng.

"If you can make quick corrections or switch to other systems, you will be able to use GNSS much more than is the case today. It will be a great advantage if a landing aircraft can use a GNSS system, for example, if there is fog in the area."

Fast analysis requires cloud-based data management

For this to be possible, the data coming from the navigation satellites must be analyzed quickly so that any disturbances or errors are notified to the end-user promptly.

However, fast handling and processing of data are needed to obtain accurate and reliable data in near real-time. Therefore, part of Lars Stenseng's work is to develop cloud-based systems to process and analyze large amounts of data and allow scaling the system to cover larger areas and regions.

"This will allow us to focus on analyzing positioning data and develop new methods rather than managing computation," says Lars Stenseng.

The longer-term perspective is to make such a basic infrastructure available to operational users.