Latest Galileo Satellites Join Constellation With Enhanced, Faster Fix
Europe’s latest Galileo satellites in space have joined the operational constellation, transmitting navigation signals to three billion users across planet Earth as well as relaying distress calls to rescuers. Their entry into service follows a summer test campaign and will result in a measurable increase in positioning accuracy and improved data delivery performance of the overall Galileo system.
“This testing was crucial for the entire Galileo system, as it means that end-users are now able to receive a first positioning fix twice as fast, down to just 16 seconds.”
Stefan Wallner, Head of the G1 Signal in Space Engineering Unit.
Galileo satellites 27-28 were launched at the end of last year and underwent their in-orbit test review at the end of April, held between ESA, satellite manufacturer OHB and navigation payload maker Surrey Satellite Technology Ltd (SSTL). Their key findings included the fact that both satellites’ payloads are performing extremely well – among the best in the entire constellation – and that both satellites entering into service increase the position accuracy and robustness of the overall Galileo system.
A successful system/operations in-orbit test review followed, co-chaired by ESA and EUSPA, the EU Agency for the Space Program, in overall charge of commissioning, which confirmed the satellites' health. Now, following a successful test campaign this summer, these two latest Galileo satellites have become the first to broadcast an improved navigation message, resulting in three key improvements for Galileo's public Open Service users.
For the testing and broadcasting of this new navigation message, new software for the Navigation Signal Generation Unit was developed by Thales Alenia Space in Italy, SSTL, OHB and ESA and was uploaded to the two satellites.
During the summer, an extensive test campaign was conducted by ESA to ensure the compatibility of the entire Galileo system at unit, payload, satellite, ground, and system levels with the enhanced message. As part of this effort EUSPA oversaw receiver testing, to ensure this compatibility extended to the Galileo receivers and chipsets in the market. These latest launched satellites made ideal test cases for the software and the improved navigation message.
“This testing was crucial for the entire Galileo system, as it means that end-users are now able to receive a first positioning fix twice as fast, down to just 16 seconds,” said Stefan Wallner, Head of the G1 Signal in Space Engineering Unit.
Transmission of the upgraded signals from the latest Galileo satellites allowed the team to confirm its correct implementation and characterize its long-term performance. Following a successful Test Review Board, the satellites were brought back into service on 29 August.
(Images provided with ESA news release)