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Alternative Position, Navigation and Timing (AltPNT)

JRC conducted testing campaigns of the mature technologies able to provide precise time and position, without use of navigation satellites. Aim is to strengthen EU economy and critical infrastructure resilience.

We are all used to maps and navigation functionalities on our mobile devices, and this make our life much easier in many occasions. This is possible thanks to Space technology, and more specifically by Global Navigation Satellites Systems (GNSS). GNSS are networks of satellites orbiting at about 20.000 km above Earth. Also EU has deployed its own GNSS, Galileo.

What might be less obvious is that such technology is not only there for consumer applications, and that many important aspects of our life actually depend on GNSS. Satellite navigation is indeed needed to keep our power grids and mobile networks working, as well as to maintain aviation, road transport and other critical infrastructures moving safely. This is possible thanks to the precise time and position distributed by Galileo and the other GNSS, like the American GPS.

We are therefore heavily dependent from space technologies, often referred to as the “invisible utility”, but as with every utility, also GNSS have inherent shortcomings, or it could be compromised by a malicious actor. While this possibility is extremely low, the effects of any outage would be far reaching and potentially very damaging to European economy.

To address this threat, it is important to consider solutions that could eventually backup in the case of need. Those technologies, providing Position, Navigation and Timing (PNT) independently from GNSS, are typically referred to with the expression “alternative PNT”, or AltPNT for short. Those technologies can provide position and time independently and can act as backup, bridging a gap in the unlikely case of a GNSS outage.

In the recent years, JRC was actively involved in the field of AltPNT on the side of DG DEFIS, with the objective of assessing technologies available at this scope. This activity was possible thanks to the long-standing involvement of JRC in the field of GNSS and satellite navigation, leading to the development of a World-class state-of-the-art laboratory, the JRC testing and demonstration hub for the EU GNSS programmes

JRC testing and demonstration hub for the EU GNSS programmes

Since many years JRC has a prominent role on the development of the European GNSS programmes, supporting DG DEFIS and EUSPA (the European Agency for the Space Programme) with specialised expertise and a dedicated laboratory and testing hub.

This JRC’s GNSS Testing and Demonstration Hub, built around the European Microwave Signature Laboratory, is located at the JRC site in Ispra, Italy.

Among many activities, the support JRC provides to EU GNSS includes:

  • Testing campaigns in the frame of H2020/Horizon Europe Calls funded under the EU Space Programme;
  • Open calls addressed to Galileo receiver Manufacturers and supporting many sectorial policies, such as eCall, Maritime receivers, Smart Tachograph, among others;
  • Programmatic actions requiring testing of GNSS user equipment (e.g., pilot testing of new EGNSS services, compatibility assessments, performance monitoring, …);

Given its extension and the variety of infrastructures present on the site, the JRC Ispra campus represents an ideal testbed for the testing and demonstration activities required to assess AltPNT technologies.

What is Alternative PNT

As previously mentioned, like the global GNSS, the technologies being assessed are meant to provide Position, Navigation and Timing. This is a combination of three distinct yet integral capabilities:

  • Positioning, the ability to determine one’s location and orientation in two or three dimensions.
  • Navigation, which is the ability to determine a path between the current and a desired position (relative or absolute), as well as navigate this path by applying corrections to course, orientation, and speed.
  • Timing, which is the ability to acquire and maintain time either locally or globally. This also needs to transfer the time information in a reliable way.

The technologies being assessed are very diverse, and typically providing either time or full PNT. Such systems are required to function independently from GNSS, being therefore able to generate and/or transmit independently time or provide position, and are therefore known as Alternative PNT (AltPNT).

Alternative PNT testing at the JRC Ispra

In 2020 DG DEFIS launched a call for tenders for the Alternative Position, Navigation and Timing (PNT) Services, with objective to understand what are the most relevant and mature technologies available at the scope. This call for tenders specified the definition of the AltPNT as mature technologies that could:

  • Deliver positioning, and/or timing information independently from GNSS;
  • Act as a backup in the unlike event of a GNSS disruption;
  • (If possible) extend PNT provision to the environments where GNSS (and Galileo in particular) cannot be delivered.

In the context of this project, JRC has tested the selected to assess the performance against the required capabilities. The testing activities were conducted over seven months and involved the assessment of the following technologies:

  • Precise time keeping using stand-alone atomic clocks and without use of GNSS.
  • Precise time transfer over long distances through fibre, computer networks and over the air, for which a Time Reference Traceability to UTC(IT) was developed. This included also a 105km time transfer over the air.
  • Indoor and outdoor positioning using terrestrial and LEO signals and tested using dynamic Reference Platform.

In order to perform those activities, many infrastructures were deployed all over the JRC Ispra campus, including dedicated beacons. Also, regulatory actions involving the Italian frequency authority were to be initiated in order to obtain the clearance for the transmission at specific regulated frequencies during the testing and within the JRC Ispra site.

Alternative PNT Demo Day, 18 May 2022

The testing campaign concluded with a Demo Day, that was held at the JRC Ispra on 18 May 2022. The event was attended by representatives from the European Commission, EUSPA, ESA and EU Member States representatives from Public Bodies and Industry. Even under COVID restrictions the event has seen the participation of over 80 people on-site, with about 90 participants joining online. The event was organized over two main sessions:

  • In the morning, after an introduction from JRC and DEFIS (including interventions from JRC.E Director and DEFIS.C.2 and JRC.E.2 Head of Units), the participants could visit the JRC laboratories and assist to a live demonstration of the technologies that were tested in the previous months.
  • In the afternoon, comprehensive presentations of the different Alternative PNT technologies and the most relevant test campaign results were provided by the various involved Industries.

The Demo Day presentations are available for download just here below.

Alternative PNT Report

A comprehensive overview of the results of the testing campaign, including most of the information presented during the Demo Day, will be made available within a dedicated JRC Science for Policy Report. The report is expected to be published in Q1 2023.

Contact Us

For more information on the testing or the alternative Position and Time activities at the JRC, please contact with the altPNT keyword in the heading