Very precise synchronization of distributed pseudolites

Pseudolites are GNSS transmitters that have a fixed position on the ground and transmit original satellite signals. Very often pseudolites are used around airports and harbors to ease the navigation and increase integrity and availability of satellite navigation systems. Pseudolites are also used in the European “Gate”- Projects. “GATE” is the name of a Galileo test bed where several pseudolites are located around a valley in southeast Bavaria transmitting Galileo signals so that receivers are able to use Galileo signals for testing purpose in “real live” before the satellites are in the sky. Besides this first Gate project a number of similar pseudolite projects have been established. One of these projects is named “aviation gate” and is located at the research airport of Braunschweig.