Good test results are always encouraging, and so it was when SSTL completed an in-orbit test campaign analyzing signals from the new GIOVE-B satellite for ESA. The results indicate that GIOVE-B is operating well and further validates all the technologies integral to the EU-funded Galileo Satellite Navigation project.
During May and June SSTL’s Galileo team processed data acquired by the Science and Technology Facilities Council (STFC) at its 25m dish in Chilbolton to analyze the center frequency, signal power and structure of all three Galileo signals. The team validated the in-orbit signals, which met expectations and correlated with ground tests before launch. Following the GIOVE-B campaign, SSTL retested GIOVE-A for ESA. The results confirm that GIOVE-A is still performing as it should five
months into its mission extension. The satellite, which was built by
SSTL, has been broadcasting navigation signals almost continuously since
January 2006.
In addition to the Galileo Binary Offset Carrier (BOC) signals transmitted by GIOVE-A, GIOVE-B is successfully transmitting the new multiplexed binary offset carrier (MBOC) signal in line with the EU-US agreement reached in 2007. The new signal supports efforts towards Galileo-GPS cooperation. Additional test results also indicate that the new hydrogen maser atomic clock onboard GIOVE-B is working correctly. The maser promises better long term stability and improved accuracy compared to the rubidium clock on board GIOVE-A.
This campaign further extends SSTL’s expertise on the Galileo program, which was demonstrated by the provision of the first Galileo satellite, GIOVE-A, in 2005, which secured the frequencies for the European program and has been continuously providing Galileo signals. SSTL recently offered ESA a reliable and cost effective approach to the further deployment of Galileo based on these successful programs.
Over the coming months SSTL intends to perform analysis of the data collected by the Standard Radiation Environment Monitor (SREM) device on board the GIOVE-B spacecraft in conjunction with the Surrey Space Centre (SSC) to characterize the little known Medium-Earth Orbit (MEO). It is hoped that GIOVE-B will provide data to complement and expand upon results from GIOVE-A, which was the first European satellite to operate in MEO.
