ESA Plans to Conduct In-Orbit Demonstration of LEO-PNT Satellites

ESA Plans to Conduct In-Orbit Demonstration of LEO-PNT Satellites

ESA’s Navigation Directorate has planned an in-orbit demonstration with new navigation satellites that will orbit just a few hundred kilometers up in space, supplementing Europe’s 23 222-km-distant Galileo satellites. Operating added-value signals, these novel so-called ‘LEO-PNT’ satellites will investigate a new multi-layer satnav system-of-systems approach to deliver seamless Positioning, Navigation, and Timing (PNT) services that are much more accurate, robust, and available everywhere.

Global in coverage, and free for everyone to use, Global Navigation Satellite Systems (GNSS) such as Europe's Galileo have already transformed our society, and due to their sheer omnipresence, their influence continues to grow. In 2021, the population of satnav receivers reached 6.5 billion receivers around the world and the sector is projected to maintain a 10% annual growth rate in the years ahead.  But in various respects the standard GNSS approach is nearing the limits of optimum performance – to get even better, added ingredients are becoming essential.

“Satellite navigation has enabled a vast range of applications in recent years, but this very success is inspiring still more demanding user needs for the coming decade,” notes Lionel Ries, Head of ESA's GNSS Evolutions R&D team, overseeing the Agency's LEO-PNT studies.

“For use cases such as autonomous vehicles, ships or drones, robotics, smart cities or the industrial Internet of Things (IIoT) for control of factory systems, the positioning requirements are growing from the current meter-scale to centimeter scale or even more precise, based on continuously reliable signals that are available anywhere, anytime – even indoors –while able to overcome interference or jamming.

“Up until now the classical solution of GNSS such as Galileo, located in medium Earth orbit and based on L-band signals, has been what we rely on for our positioning. Standard GNSS alone is not going to be able to fulfill all these future user demands. Instead, Europe needs to seize the opportunity to investigate the potential of the kind of low Earth orbit (LEO) constellations that are already on the way in the global market to enable new kinds of Positioning, Navigation, and Timing (PNT) services.”

Simply by virtue of physics, with less of a distance to cover down to Earth, the signals from these LEO-PNT satellites can be more powerful, able to overcome interference and reach places where today’s satnav signals cannot reach.

And by adopting novel navigation techniques and a wider range of signal bands the satellites can address particular user needs: for instance at lower orbits the satellites themselves move more rapidly relative to Earth’s surface – think of the International Space Station at 400 km that orbits the Earth every 90 minutes – which offers a possible advantage in the time needed to reach very accurate positions. Also, some bands could offer greater penetration in difficult environments while other bands could offer higher robustness and precision.

The purpose of ESA’s plan to perform an in-orbit demonstration of low Earth orbiting satnav satellites is precisely to consolidate the types of signals, enabling technologies, and their potential for future services.

The plan is to build and fly an initial mini-constellation of at least half a dozen satellites to test capabilities and key technologies, as well as demonstrate signals and frequency bands for use by a follow-on operational constellation, in the same way, that Europe’s GIOVE test satellites paved the way for Galileo. Success will place European industry in pole positions for follow-on commercial undertakings, as well as planned institutional programs.

“Each individual satellite would be comparatively small, below 70 kg in mass, compared to a 700 kg current Galileo operational satellite,” adds Roberto Prieto-Cerdeira, Galileo Second Generation Satellite Payload Manager, and LEO-PNT project preparation manager as part of ESA’s FutureNAV program.

“They can be comparatively more streamlined because they can benefit from other means to calculate the accurate time without extremely precise atomic clocks on board – including relayed signals from the Galileo satellites above them. These satellites would also be built on a rapid batch production basis to save time and cost – we are targeting three years at the most from signing the contracts to the first satellites in orbit, the same kind of timescale achieved by GIOVE-A in the early 2000s.”

“It is ESA’s ambition to ensure Europe maintains a world-class space industry, and navigation today forms the single largest downstream space sector, worth about €150 billion annually and growing at the rate of 10% per year,” comments ESA Director of Navigation Javier Benedicto-Ruiz. “Standing still is not an option; instead we need to explore new technical avenues to spur European competitiveness and commercialization.”

An operational version of the LEO-PNT constellation would represent a whole new layer for PNT delivery, combined with traditional GNSS as well as 5G/6G-based positioning on the ground, and fused with data from sensors in the user terminals.

Click here to learn about the European GNSS Evolution Programme (EGEP).

Publisher: SatNow
Tags:-  SatellitePNTGNSSLEOGlobal

GNSS Constellations - A list of all GNSS satellites by constellations


Satellite NameOrbit Date
BeiDou-3 G4Geostationary Orbit (GEO)17 May, 2023
BeiDou-3 G2Geostationary Orbit (GEO)09 Mar, 2020
Compass-IGSO7Inclined Geosynchronous Orbit (IGSO)09 Feb, 2020
BeiDou-3 M19Medium Earth Orbit (MEO)16 Dec, 2019
BeiDou-3 M20Medium Earth Orbit (MEO)16 Dec, 2019
BeiDou-3 M21Medium Earth Orbit (MEO)23 Nov, 2019
BeiDou-3 M22Medium Earth Orbit (MEO)23 Nov, 2019
BeiDou-3 I3Inclined Geosynchronous Orbit (IGSO)04 Nov, 2019
BeiDou-3 M23Medium Earth Orbit (MEO)22 Sep, 2019
BeiDou-3 M24Medium Earth Orbit (MEO)22 Sep, 2019


Satellite NameOrbit Date
GSAT0223MEO - Near-Circular05 Dec, 2021
GSAT0224MEO - Near-Circular05 Dec, 2021
GSAT0219MEO - Near-Circular25 Jul, 2018
GSAT0220MEO - Near-Circular25 Jul, 2018
GSAT0221MEO - Near-Circular25 Jul, 2018
GSAT0222MEO - Near-Circular25 Jul, 2018
GSAT0215MEO - Near-Circular12 Dec, 2017
GSAT0216MEO - Near-Circular12 Dec, 2017
GSAT0217MEO - Near-Circular12 Dec, 2017
GSAT0218MEO - Near-Circular12 Dec, 2017


Satellite NameOrbit Date
Kosmos 2569--07 Aug, 2023
Kosmos 2564--28 Nov, 2022
Kosmos 2559--10 Oct, 2022
Kosmos 2557--07 Jul, 2022
Kosmos 2547--25 Oct, 2020
Kosmos 2545--16 Mar, 2020
Kosmos 2544--11 Dec, 2019
Kosmos 2534--27 May, 2019
Kosmos 2529--03 Nov, 2018
Kosmos 2527--16 Jun, 2018


Satellite NameOrbit Date
Navstar 82Medium Earth Orbit19 Jan, 2023
Navstar 81Medium Earth Orbit17 Jun, 2021
Navstar 78Medium Earth Orbit22 Aug, 2019
Navstar 77Medium Earth Orbit23 Dec, 2018
Navstar 76Medium Earth Orbit05 Feb, 2016
Navstar 75Medium Earth Orbit31 Oct, 2015
Navstar 74Medium Earth Orbit15 Jul, 2015
Navstar 73Medium Earth Orbit25 Mar, 2015
Navstar 72Medium Earth Orbit29 Oct, 2014
Navstar 71Medium Earth Orbit02 Aug, 2014


Satellite NameOrbit Date
NVS-01Geostationary Orbit (GEO)29 May, 2023
IRNSS-1IInclined Geosynchronous Orbit (IGSO)12 Apr, 2018
IRNSS-1HSub Geosynchronous Transfer Orbit (Sub-GTO)31 Aug, 2017
IRNSS-1GGeostationary Orbit (GEO)28 Apr, 2016
IRNSS-1FGeostationary Orbit (GEO)10 Mar, 2016
IRNSS-1EGeosynchronous Orbit (IGSO)20 Jan, 2016
IRNSS-1DInclined Geosynchronous Orbit (IGSO)28 Mar, 2015
IRNSS-1CGeostationary Orbit (GEO)16 Oct, 2014
IRNSS-1BInclined Geosynchronous Orbit (IGSO)04 Apr, 2014
IRNSS-1AInclined Geosynchronous Orbit (IGSO)01 Jul, 2013