GIOVE

In 2004 the Galileo System Test Bed Version 1 (GSTB-V1) project validated the on-ground algorithms for Orbit Determination and Time Synchronization (OD&TS).

Previous SSTL satellites use body-mounted solar arrays, which generate less power per unit area as they do not face the Sun directly.

The launch was delayed due to various technical problems,[10] and took place on 27 April 2008 at 04:16 Baikonur time (22:16 UTC Saturday) aboard a Soyuz-FG/Fregat rocket provided by Starsem.

[13] According to ESA, this is "a truly historic step for satellite navigation since GIOVE-B is now, for the first time, transmitting the GPS-Galileo common signal using a specific optimised waveform, MBOC (multiplexed binary offset carrier), 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".

Chilbolton's 25-metre antenna makes it possible to analyse the characteristics of GIOVE-B signals with great accuracy and verify that they conform to the Galileo system's design specification.

The quality of the signals transmitted by GIOVE-B will have an important influence on the accuracy of the positioning information that will be provided by the user receivers on the ground.

On board, GIOVE-B carries a passive hydrogen maser atomic clock, which is expected to deliver unprecedented stability performance.

Additionally, the satellite signals must not create interference with services operating in adjacent frequency bands, and this is also being checked.

Galileo teams within ESA and industry have the means to observe and record the spectrum of the signals transmitted by GIOVE-B in real time.

The GIOVE-B mission also represents an opportunity for validating in-orbit critical satellite technologies, characterising the Medium Earth Orbit (MEO) radiation environment, and to test a key element of the future Galileo system - the user receivers.

With the delays of GIOVE-B, the European Space Agency again contracted with SSTL for a second satellite, to ensure that the Galileo programme continues without any interruptions that could lead to loss of frequency allocations.

[2] The GIOVE Mission was intended to ensure risk mitigation of the In Orbit Validation (IOV) phase of the Galileo positioning system.