Method and device method for detecting frequency jumps of a navigation satellite's master clock
AssigneeAstrium GmbH
InventorVeit Oehler
Life of this patent
Estimating the term…
Abstract
A method for detecting frequency jumps of a navigation satellite's master clock, comprising the steps of i) monitoring the master clock signal that is generated by a master clock onboard of the satellite for a frequency jump, and ii) signaling a detected frequency jump of the master clock signal.
Claims15
A method for enhancing integrity performance of a global navigation satellite system that includes a plurality of navigation satellites, each of which has a master clock, said method comprising:
- on board at least one of said satellites, monitoring a master clock signal generated by the master clock onboard said at least one of the satellites using a clock monitoring and control unit, to detect a frequency jump, wherein the monitoring comprises comparing a frequency of an untransmitted master clock signal with a frequency of an untransmitted backup clock signal;
- and
- said at least one of the satellites signaling a detected frequency jump of said master clock signal.
A method for enhancing integrity performance of a global navigation satellite system that includes a plurality of navigation satellites, each of which has a master clock, said method comprising:
- on board at least one of said satellites, monitoring a master clock signal generated by the master clock onboard said at least one of the satellites, to detect a frequency jump;
- and
- said at least one of the satellites signaling a detected frequency jump of said master clock signal,
- wherein said monitoring comprises
- comparing the frequency of an untransmitted master clock signal with the frequency of an untransmitted backup clock signal, which is generated by a backup clock, onboard said at least one of the satellites, for detecting a frequency jump of a clock signal;
- comparing a detected frequency jump with a threshold;
- and
- if the detected frequency jump exceeds the threshold, generating a frequency jump detection event,
- wherein the comparing step comprises
- estimating the frequency of each of said clock signals based on phase measurement values of the respective clock signal;
- and
- comparing the estimated frequencies of both clock signals;
- wherein the comparing of a detected frequency jump with a threshold comprises,
- detecting a difference between the estimated frequencies;
- comparing the detected difference with the threshold;
- and
- generating the frequency jump detection event if the detected difference exceeds the threshold.
Apparatus for detecting frequency jumps of a navigation satellite's master clock, said apparatus comprising:
- a clock monitoring and control unit that monitors a master clock signal generated by the master clock onboard the satellite, for a frequency jump by comparing a frequency of an untransmitted master clock signal with a frequency of an untransmitted backup clock signal;
- and
- a frequency jump signaling unit which signals a detected frequency jump of the master clock signal.
Dependencies are inferred from the claim text.