On 7 May the GIOVE-B satellite began transmitting navigation signals, marking an historic step for satellite navigation. For the first time, it is transmitting the GPS-Galileo common signal using a specific optimized waveform, Multiplexed Binary Offset Carrier (MBOC), in accordance with the agreement drawn up in July 2007 by the EU and the US for their respective systems, Galileo and the future GPS III.

These GIOVE B signals, locked on-board to a highly stable passive hydrogen maser clock, will provide higher accuracy in challenging environments where multipath and interference are present and deeper penetration for indoor navigation. It demonstrates that Galileo and GPS are truly compatible and interoperable and that positioning services will benefit all users worldwide.

Galileo project manager, Javier Benedicto, stated, “Now with GIOVE B broadcasting its highly accurate signal in space we have a true representation of what Galileo will offer to provide the most advanced satellite positioning services, while ensuring compatibility and interoperability with GPS."

Following the commencement of signal transmission the quality of the signals is being checked. Several facilities are involved in this process, including the GIOVE B Control Centre at Telespazio facilities in Fucino, Italy, the Galileo Processing Centre at ESA’s European Space Research and Technology Centre (ESTEC), in the Netherlands, the ESA ground station at Redu, Belgium, and the Rutherford Appleton Laboratory (RAL) Chilbolton Observatory in the UK.