Galileo and the Other Satellite Navigation Systems

GPS is the best-known satellite navigation system in the world. Next to GPS, a Russian system GLONASS is operating, and a European system Galileo is intensively prepared. The first satellite of the Galileo system should be launched in 2009, and the whole system Galileo should start to regularly operate in 2011 or 2012. Both in the community of researchers and in the public, questions about the accuracy, compatibility and helpfulness of those systems are discussed. Those questions are not only of the technical nature but also of the political one. The paper tries to give explanation of the principles of the operation of those systems, and their mutual comparison. At the end of the paper a concept of satellite navigation receiver designed at the Czech Technical University in Prague is sketched.