RUAG Space has received funding from GSA, the European GNSS Agency, to develop a GNSS (Global Navigation Satellite System) receiver for Low Earth Orbit satellites. The project aims to develop a GNSS receiver for Low Earth Orbit (constellation) satellites in the 50–500 kg class for space applications with Precise Point Positioning (PPP) capability. The receiver will be based on Galileo’s E6 High Accuracy Service (HAS). The service provides real-time positioning accuracy in the low decimeter or even centimeter range.
Galileo’s HAS is expected to be a game changer for real-time navigation in space. With the advent of HAS it will be possible to perform PPP processing without relying on services so far exclusively offered by commercial PPP providers.
The project intends to close a significant technology gap for GNSS receivers through:
- Leveraging the unique Galileo high accuracy service
- Precise positioning and precise and robust timing using wide bandwidth E-GNSS signals
- Dual and triple frequency operation of the GNSS receiver
- Satellite-based real-time Precise Point Positioning (PPP) without commercial correction services
The project’s goal is to develop a GNSS receiving system that is also geared towards the New Space market. The system should be capable of the Precise Point Positioning (PPP) technique utilizing Galileo’s High Accuracy Service (HAS) transmitted on the Galileo E6 signal. “New Space” is this context mainly refers to a major trend in space to change from large, expensive satellites to constellations of smaller, cost optimized satellites. This trend is seen in telecommunication applications, where hundreds or even thousands of satellites are planned to replace the large GEO satellites used in previous decades. The most well-known examples of such constellations are OneWeb, Telesat, Amazon’s Kuiper and SpaceX’s Starlink, but there are also several other telecom constellations planned.
To the Benefit of Humankind
Satellite (constellations) enabled by PPP navigation allow for a number of applications that have a major benefit for humankind. Those include climate research, numerical weather prediction, safety of life services, satellite collision avoidance and in-orbit satellite servicing:
- Earth observation: will be done by constellations at much reduced re-visit time. PPP navigation therefore supports not only high spatial resolution but also much improved time resolution, which is increasingly judged by scientists to be at least as valuable as higher spatial resolution.
- Climate (change) monitoring: depends on the fusion of a lot of earth observation sensor data that is distributed on ground, at sea, in the air and space. Even if these sensors provide sufficient accuracy and stability for long time climatological monitoring, data fusion is only possible if the time and position of the data takes are accurately determined. For that common reference frames are needed as supported by the proposed Galileo receiver.
- Improved Efficiency: By elevating navigation to previously unreachable accuracy, LEO orbit (position) resources can be used with much higher efficiency by many small satellites, for example in constellations. This leads to lower operation cost and significantly reduced collision risk.
- Economic Development: Telecom constellations providing communication on a global scale foster local business thanks to global connectivity. This provides work and income and generally drives economic growth in otherwise underdeveloped regions of the world.
- Saving Lives: beforehand unavailable communication with emergency services will allow to reduce lead time of first responders. Even in densely settled areas with good telecommunications infrastructure, satellite communication systems with low latency as offered by LEO constellations will be beneficial to back terrestrial 5G networks. They allow for the interconnection of all the foreseen services.
- In-Orbit Servicing: High-performance GNSS receivers are used also on board of satellites designed for in- orbit servicing of other satellites.
