How to navigate on the moon?

Last Updated: 24/04/2023 08:51     Created at: 24/04/2023 08:47

Final Presentation of NAVISP Project EL1 023 now available:

On Thursday, April 20th, 2023, Space PNT presented, together with its consortium partner from the University of Nottingham and Harp Technologies Ltd the results of the NAVISP EL1 023 project "Earth Moon Navigation / System Study and Development of Highly Sensitive Spaceborne receiver prototype". About 90 people from industry and research institutes followed the interesting presentation and the subsequent interactive Q&A session.

Exploring the Moon is emerging as the next global strategic priority in space exploration, with very ambitious government and commercial missions in the coming decades for a permanent return of mankind to the Moon. Plans call for a dedicated infrastructure of satellites around the Moon to provide communications and navigation services, unlocking the potential for future lunar missions to deliver more data through high-rate, low-latency communications, better and safer landing and navigation capabilities, and less on-board complexity.

The possibility of extending GNSS for missions to the Moon was preliminarily assessed by ESA in the recent past concluding that navigation to the Moon using GNSS complemented by other instruments could be feasible, provided specific high-sensitivity techniques are implemented in receivers. The availability of a positioning, navigation, and timing (PNT) service for the Earth-Moon system in the near future is supported by both institutional and commercial initiatives, as currently developed lunar business models increasingly demonstrate (e.g., proposals for tourism applications or lunar mining).

In this context, the objective of the activity was to assess in detail the feasibility and associated achievable performance of a complete PNT system using current GNSS signals from multiple constellations for Earth-Moon missions.

More specifically, the main objectives of the NAVISP EL1 023 activity were twofold:

• To study the use of multi-constellation GNSS for Earth-Moon missions, confirming feasibility, assessing achievable performance and identifying a preliminary architecture with possible enhancements to existing GNSS constellations;
• To develop a GNSS spaceborne receiver prototype as a technology risk mitigation for future application in demonstration missions and in order to gather data and support further system activities.

The first part of the project, the feasibility study, explored various scenarios, including consolidating user requirements and investigating the navigation performance of lunar missions using GNSS signals. This was extended by investigating performance improvement through augmentation satellites. In this phase, it was concluded that augmentation in conjunction with adaptive orbit filters could be very useful, with the potential to enable better performance.

Building on these findings, a steerable dual-band GNSS antenna was designed and the NaviMoon multi-constellation, multi-frequency GNSS receiver was developed as an evolution of SpacePNT's flagship spaceborne GNSS receiver, NaviLEO.

This activity, together with the related  NAVISP Project EL1 039, are important foundations for ESA's Moonlight initiative. As a matter of fact, the refined version of this receiver will be on board the Lunar Pathfinder satellite, scheduled for launch in 2025.

The project was carried out in the scope of NAVISP Element 1, which is dedicated to technology innovation of the European industry in the wide PNT sector.

More detailed information can be found in the slides of the Final Presentation.