Abstract: In a system for characterizing a satellite clock in a satellite, the satellite has a transmitting device that emits a transmission signal at a transmission frequency indicative of a state of the satellite clock, and a receiver clock which has a higher precision than the satellite clock. A receiving device is configured to receive the transmission signal and to determine a received signal therefrom, as well as a received signal frequency and/or phase, using the receiver clock. Finally, an evaluation device is configured to determine a frequency offset, drift, and/or an Allan deviation of the transmission frequency from the received signal frequency and/or the received signal phase. The evaluation device determines the stability of the satellite clock, or the validity of its time indication, from the determined frequency offset, frequency drift, and/or the Allan deviation, to thereby characterize the satellite clock.

Abstract: In a system for characterizing a satellite clock in a satellite, the satellite has a transmitting device configured to emit a transmission signal at a transmission frequency as a function of a state of the satellite clock. The system includes a receiver clock which has a higher precision than the satellite clock. In addition, a receiving device is configured to receive the transmission signal and to determine a received signal therefrom, as well as a received signal frequency and/or phase, using the receiver clock. Finally, an evaluation device is provided which is configured to determine a frequency offset, drift, and/or an Allan deviation of the transmission frequency from the received signal frequency and/or the received signal phase. The evaluation device determines the stability of the operation of the satellite clock or the validity of the time indication of the satellite clock from the determined frequency offset, frequency drift, and/or the Allan deviation, to thereby characterize the satellite clock.