Galileo signal component tested for Internet of Things use

The meter-level accuracy provided by Galileos Open Service makes it the most accurate generally available service in the world, surpassing other global navigation systems such as GPS and providing not only positioning, navigation and timing services to users worldwide, but also helping rescue missions. However, individual satellites within the constellation can also be used to test new signals and services as the system continues to progress.

The Internet of Things brings new needs

On the way are integrated sensors placed in everything from household appliances to agricultural equipment to smart city infrastructure, allowing those items to report and exchange information about their location so they can work together. At the same time, these autonomous sensors are constrained by strict limits on available battery power and computational resources.

To serve this emerging market of Internet of Things and snapshot devices and to address the needs of chipset manufacturers, Galileo engineers therefore considered the need for a positioning signal that can be acquired with less computational complexity.

Test the new signal component

This new ESA-developed E5-band test signal component is located along a narrow stretch of the overall Galileo signal, intended to allow for simplified positioning corrections that require fewer calculations, with no effect on the E1 and E6 signal bands on which Galileo transmit. Preliminary receiver test performance demonstrated that the signal component has the potential to reduce signal acquisition time by a factor of three compared to current L5 GPS or Galileo E5a signals.

Until now, no other global navigation satellite system has provided such capability in the E5 frequency band, but the emerging market prospect for such a capability is clear, comments Jrg Hahn, head of the first generation Galileo system engineering service at the ESA. With the reconfiguration of the satellites it would be possible to distribute this new capacity to the entire constellation in a relatively short time, responding directly to current user demand.

One of Galileo’s elliptical orbit satellites officially known as GSAT0202 was reconfigured in January to broadcast this new signal component in the E5 band for testing purposes.

Once the satellite was reconfigured, signal measurements were made using high-gain antenna installations from the ESA Center’s Galileo in-orbit test facility in Redu, Belgium and the German Aerospace Center’s signal monitoring facility DLR in Weilhelm, Germany, confirming the stability of the augmented signal.

Then, soon after the component of the test signal was transmitted, it was successfully acquired and tracked by a series of receivers located at ESA’s navigation laboratory, based at its ESTEC technical center in the Netherlands.

Successful preliminary test of the signal component

The successful start of this test campaign is the result of intensive design and testing activities, adds Stefan Wallner, head of ESA’s Galileo First Generation Signal in Space Engineering Space Engineering Unit. Thanks to the great engineers supporting Galileo within ESA and on the industrial side, it has been possible to introduce this new test signal on board a satellite that was not initially designed to accommodate such a capability. We’ve now tested this new signal component in a lab setting, so we were eager to see how it performs in a real-world setting.

The work was supported by a number of industrial partners including Airbus Defense and Space, Thales Alenia Space Italia, as well as EUSPA, the EU Space Program Agency which oversees the delivery of Galileo services the European Commission, the of the Galileo program – and Spaceopal, Galileo operative.

After detailed tests to show the value of the so-called G1 E5 Quasi Pilot signal component, in the next phase the other elliptical Galileo satellite GSAT0201 will be similarly reconfigured, while selected chipset manufacturers will be involved in the tests under the supervision of EUSPA. The results of the test will be evaluated at the Galileo Program level to evaluate the introduction of this new signal component in the constellation.

About Galileo

Galileo is currently the most accurate satellite navigation system in the world and serves almost four billion users worldwide since it entered Open Service in 2017. All smartphones sold in the European single market are now guaranteed Galileo-enabled. In addition, Galileo is making a difference in the railway, maritime, agricultural, financial timing services and rescue operations sectors

Galileo is one of the flagship programs of the EU space programme, managed and funded by the European Union. From the outset, ESA has led the design and development of ground and space systems, as well as the procurement of launches. EUSPA (the EU’s Space Program Agency) acts as Galileo’s service provider, overseeing market and application needs and closing the loop with users.