This week marks another important milestone for the Galileo project, with its ground segment formally gaining a brand-new asset.

Galileo’s Telemetry, Tracking and Control (TT&C) facility is a 13.5-meter diameter parabola dish mounted on top of a 10-meter-high building structure of steel and concrete. Known as the acronym TTCF-7, it is based within the premises of Europe’s launch site in Kourou, French Guiana, beside its older sibling TTCF-2.

“It has taken several months of intense, very demanding work to complete this highly sophisticated asset,” comments ESA Technical Officer Bobby Nejad, coordinating with the GMV, Indra Sistemas and CPI Vertex Antennentechnik GmbH companies responsible for the antenna’s design, development, and on-site deployment.

“A big part of the challenge come from its location; we needed to get it working flawlessly in a hot and humid environment beside the Amazon rainforest before handing it over to its operator. Its entry into service has been eagerly awaited, providing sufficient spare capacity to modernise the rest of the ground segment and keep up with the needs of the Galileo constellation in space as it continues to grow.”

With 28 satellites flying in orbit, Galileo has grown to become Europe’s single biggest public satellite constellation, and it continues to grow with 10 more satellites on the ground due to be lifted into space.

Each Galileo satellite requires regular ground contacts to gather its housekeeping telemetry and receive new telecommands to continue its mission. TT&C antennas are built for exactly that purpose and are therefore an indispensable element of every satellite ground infrastructure.

These Galileo antennas are uncrewed, operated on a fully automated basis from the two Galileo Control Centres (GCCs) which are located several thousand kilometres away in Oberpfaffenhofen Germany and Fucino in Italy.

Galileo’s other stations are TT&C distributed over the entire globe at remote locations like Noumea and Papeete in the South Pacific, Redu in Belgium, La Réunion close to Madagascar, and a high-latitude site at Kiruna in northern Sweden.

This latest antenna will also play an important role during the upcoming modernisation activities of the earlier TT&C antennas in the station network, which have already been in service for several years. TTCF-7 will take over their tasks during the maintenance activities when they need to be taken offline.

The challenge will only grow as the remaining Galileo First Generation satellites will be launched in the next few years, ahead of the follow-on Galileo Second Generation models.

Galileo’s ground segment is one of the most complex developments ever undertaken by ESA. It is not only challenging due to its size, technical performance, and wide geographical distribution, but it also having to fulfil very stringent reliability and security requirements to make the delivered navigation service attractive and competitive, but even more importantly, safe for the end user.

The European Union for the Space Programme, EUSPA, oversees all operational activities that make use of the ground segment as part of its responsibility for Galileo operations.

It is the accuracy, timeliness, and reliability of a robust ground segment deployed over the entire world, able to seamlessly interact with the space segment that enables Galileo to be the world’s most accurate satellite navigation system delivering metre-level precision for its more than four billion users around the globe.