Today with GPS a broad public has access to a widely available and easy to use location and navigation system. E.g. many cars have a navigation system on board that makes it easier and faster to find a special location. But with GPS, navigation stops where GPS is not available as inside buildings or in big cities where the signal is blocked by high-rise buildings. Today other manmade points of reference than satellites such as broadcast stations for mobile communication exist. In many cases a continuing navigation system for pedestrians that has to fulfill other requirements would be desirable. Especially inside buildings, where GPS is not available there is a gap for precise reliable possibilities to locate and track persons or objects or to guide a user through the building according to his needs. An active RFID system is an option to close this gap. This work presents such a location system based on radio frequency identification (RFID) to locate objects inside a building. The results of studies about the system precision and possible applications are presented in this paper.