Oct 24th 2024: The final presentation of the ESA project “Earth Moon GNSS Spaceborne Receiver For In-Orbit Demonstration” led by SpacePNT as prime with EECL as subcontractor was delivered online following an introduction from ESA representatives.
Current GEO and GTO missions already exploit GNSS signals for in-orbit PNT. NASA’s MMS mission has recently demonstrated that tracking of GPS signals is possible up to 150,000 km from Earth surface (half-way the distance to the Moon). The feasibility of extending the use of GNSS for missions to the Moon has also preliminarily been assessed by ESA in previous studies. These preliminary studies have concluded that navigation to the Moon using GNSS may be feasible, if specific high sensitivity techniques are implemented in GNSS spaceborne receivers. Multiple publications, in some cases complemented by tests with hardware in the loop, have demonstrated the potential for 100-200 metre accuracy of the orbit determination performance at Moon altitude using standalone GNSS.
The objectives of this activity were to develop and qualify a GNSS spaceborne receiver for lunar applications, including procurement of antenna and auxiliary components. The test campaign involved radiation tests, mechanical tests, thermal vacuum tests, EMC tests, and functional and performance tests. The environmental test campaign was all successful and the target accuracy (100m, 0.1 m/s) was even exceeded with a large margin (42 m, 0.02 m/s).
The results of the activity will enable the developed GNSS receiver technology to be used for orbit determination, velocity and time estimation of spacecrafts orbiting to / from and around the Moon; reducing operational costs of lunar missions, avoiding implementation of specific Earth-to-Space links.
This project was funded under ESA’s NAVISP program, dedicated to European industrial technology innovation in the PNT sector, and supported by ESA’s Swiss and UK delegations.
Photo credit: SpacePNT, ESA