GPS World • July 2022 • SYSTEM OF SYSTEMS

NASA’s Lunar GNSS Receiver Experiment (LuGRE) pay l oad will test a powerful new moon navigation capability using Earth’s GNSS signals.

Through NASA’s Commercial Lunar Payload Services initiative, Firefly Aerospace will deliver an experimental payload to the Moon’s Mare Crisium basin.

LuGRE — developed in partnership with the Italian Space Agency (ASI) — will receive signals from both GPS and Galileo, and then use them to calculate the first-ever GNSS location fixes in transit to the Moon and on the lunar surface.

In 2016, NASA’s Magnetospheric Multiscale Mission (MMS) employed GPS operationally at a record-breaking 43,500 miles from Earth. Then, in 2019, MMS broke its own record by fixing its location with GPS at 116,300 miles from Earth — nearly halfway to the Moon.

At these extreme altitudes, missions need extremely sensitive GNSS receivers. The LuGRE mission will use a specialized weak-signal receiver developed by Qascom and funded by ASI.

LuGRE teams are now testing the payload, which will then be integrated onto Firefly’s “Blue Ghost” lander in November. Launch is slated for no earlier than 2024 from Cape Canaveral, Florida, aboard a SpaceX Falcon 9 rocket.

During the multi-week flight to the Moon, LuGRE will collect GNSS signals and perform navigation experiments at different altitudes and in lunar orbit. After landing, LuGRE will deploy its antenna and begin 12 days of data collection, with the potential for extended mission operations. NASA and ASI will process and analyze data downlinked to Earth, and then share results publicly.

Nikolina Enters Service as Part of Galileo

After a challenging Launch and Early Orbit Phase (LEOP) and testing campaign during the COVID-19 pandemic, Galileo satellite “Nikolina” (GSAT0223) entered service on May 5. The satellite will reinforce the performance and robustness of the Galileo constellation.

GSAT0223 was launched Dec. 5, 2021, with Galileo launch L11 after the usual design, acceptance, validation, launch and early orbit preparation and operations phases.

This was the first Early Orbit Operations phase conducted directly from the operational center in Germany, under the responsibility of EUSPA.

GSAT0223 and its launch companion GSAT0224 (Shriya) are the first pair of the third batch of Galileo First Generation satellites to reach space. GSAT0223 will fill the last empty slot in Galileo’s orbital plane B.

Shriya will soon complete its in-orbit validation and will then join the operational constellation. Ten additional satellites of the same batch are continuing assembly, acceptance and launch preparations.

GPS III 05 Set Healthy for Operational Use

The fifth GPS III satellite is now set healthy for initial operational use, according to the U.S. Coast Guard Navigation Center (NAVCEN). GPS III 05 (SVN-78/PRN-11) was launched June 17, 2021, from Space Launch Complex-40 at Cape Canaveral Air Force Station, Florida.

Constellation Changes. The U.S. Space Force Second Space Operations Squadron (2 SOPS) indicates that GPSIII 05 replaced SVN-61/PRN-28 in the D plane at slot D1.

SVN-61 is being rephased to optimize its position in the D plane and is expected to complete its journey on or about July 14.

ICD Published for Galileo High Accuracy Service

The EU Agency for the Space Programme (EUSPA) has published the first Galileo High Accuracy Service Signal in Space Interface Control Document (HAS SIS ICD). The HAS SIS ICD was published by EUSPA together with the European Commission and the European Space Agency (ESA).

By providing free-of-charge, high-accuracy precise point positioning (PPP) corrections through both the Galileo signal (E6-B) and via the internet, the HAS will offer users improved positioning performance with an accuracy of less than two decimeters.

“Galileo will be the first GNSS constellation capable of providing a high-accuracy service directly through the signal in space,” explained Guerric Pont, Galileo Services, EUSPA program manager. “This is unique in that, typically, high-accuracy services are based on accurate satellite and atmospheric data provided from a third party, but not directly from the GNSS.”

According to Pont, high-accuracy services are experiencing a massive boost in interest, thanks in large part to new capabilities of GNSS receivers and the rapid emergence of new applications that require accurate location data.

“Currently, high accuracy is primarily used in such professional applications as surveying, precision agriculture and civil engineering, among others,” he said. “However, new and emerging applications, including autonomous driving, unmanned vehicles, robotics and a range of location-based services, will all welcome high accuracy.”

Pont also noted that, when used in synergy with Copernicus, the Galileo HAS will open market possibilities and help design new services.

NAVCEN Website Redesigned

The NAVCEN website (navcen.uscg.gov) has been upgraded and redesigned. While the primary URL remains the same, all sub-URLs have changed with the transition. Use of any bookmarked legacy URLs will result in broken links, including PDFs and URLs used in automatic downloading of data and products. “We appreciate your patience in re-bookmarking your favorite pages when we update the site,” said Stephanie Southwick, NAVCEN web team.

The NAVCEN outreach team will work with users to ensure transition to using the redesigned site is as seamless as possible. Communicate with the team at NAVCENWebTeam@uscg.mil with questions or to request additional information.