Galileo’s main “L-band” antenna (1200-1600 MHz) had the turn of sending the first signal first thing in the morning on Saturday 10 December. The first Galileo satellite transmitted a test signal in the “E1” band, which will be used by theopen serviceGalileo once began operating in 2014. To prepare for testing, before the start of transmission the payload power amplifiers were turned on, and heated to release vapors that could interfere with operations.
In Redu, waiting for the signal, a 20 meter diameter L-band antenna was ready. This antenna is an essential element in the Galileo tests, since it evaluates the shape and quality of the navigation signal even when the satellite is 23,222 kilometers high.
Signal strength and shape perfectly met specifications. The shape is especially important because its modulation is carefully designed to allow interoperability with the L1 band of the satellites of the US GPS navigation system. Indeed,Galileo and GPS were found to be able to work together, as planned.
The current test campaign focuses on the first satellite; in early 2012 the focus will be on the second Galileo satellite. These In-Orbit Testing are expected to conclude in the spring.
