Satellites are crucial in providing important data for climate and environmental research, such as how high sea levels are rising or what effects global warming is having on glacier retreats in the Alps. The precision of satellite date directly affects the scientists’ prediction.
“The more accurately the satellite’s position can be determined, the more precise the environmental data it collects and provides. This potentially unlocks new observations and predictions essential to cope with the effects of climate crisis, for example in exposed coastal cities such as Venice,” explained Fiammetta Diani, Head of Market Development at the European Union Agency for the Space Programme (EUSPA).
The Swiss company RUAG Space is working on a study for the European Union to determine the position of satellites more precisely and recently conducted its first tests on Earth. Heinz Reichinger, Technical lead engineer for navigation receivers and signal processing reported about impressive results that the company achieved with the tests. “We were able to determine the satellite’s position ten times more accurately than previously possible.” Position accuracy improved from about 100 centimeters to 10 centimeters, which even exceeded the original expectations of accuracy of 20 centimeters.
The higher accuracy was achieved with a new software program. In addition to conventional signals, the software can also process an additional position signal from the European Global Navigation Satellite System, Galileo. To determine the exact position of satellites, RUAG Space’s latest navigation receivers combine signals from both Galileo and the American GPS system. “We are using the Galileo signal to position satellites that are in space. But there is currently untapped potential in the Galileo satellites as they transmit signals in several frequency bands,” explained Martin Auer, who is leading the study at RUAG Space. With the Galileo High Accuracy Service (HAS), Galileo will pioneer a worldwide, free high-accuracy positioning service aimed at applications that require higher performance such as drones or autonomous vehicles. This service should be available in 2022.
“A software update can be played on navigation receivers already in space as well as receivers we’ve already delivered to customers and are still on Earth.” The hardware of the devices remains unchanged. ESA, for example, is having the RUAG Space navigation receiver “PODRIX” already delivered to it for the Sentinel-1C environmental satellite upgraded with this new software for in-orbit validation of the satellite. The Sentinel-1C satellite built by Thales Alenia Space will be launched in 2022.
More accurate data about a satellite’s position also helps prevent satellites from colliding in space, thus providing better space situational awareness (SSA). When satellites collide in orbit, a lot of satellite debris is created. Due to the high speed in orbit, even the smallest debris particles pose a huge threat to other satellites. “The more precise the position of a satellite is known, the better a potential accident can be predicted and, for example, evasive manoeuvres can be carried out. Our more accurate satellite positioning data helps to avoid space debris,” emphasized Heinz Reichinger.