Van Allen radiation belt
In November 2014, ESA announced the satellites would perform a total of 15 orbital maneuvers to raise their perigee to 17,339 km. This would reduce the satellites' exposure to the Van Allen radiation belt, reduce the doppler effect, increase satellite visibility from the ground, and allow the satellites to keep their antennas pointed at Earth during perigee. These orbits would repeat the same ground track every 20 days, allowing synchronization with other Galileo satellites which repeat the same ground track every 10 days. Once in their new orbits the satellites could begin in-orbit testing.