IP Library › Granted Patent US 12,320,903
Granted Patent B2
US 12,320,903 · App. 17/975,935 · Granted Jun 3, 2025

Multiple and cascaded redundant disciplined oscillator systems in a spoofing resistant reference time source system and methods thereof

Inventors: David Sohn (Pittsford, NY); John Fischer (Corfu, NY); Matthias Lorentz (Choisel, FR)
Assignee: Orolia USA Inc.
G01S19/215G01S19/23H04B17/29
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Quick Facts
Patent No.
US 12,320,903
App. No.
17/975,935
Granted
Jun 3, 2025
Kind
B2
Abstract

A system, non-transitory computer readable medium, and method include entering redundant oscillators and a cascaded oscillator of a spoofing resistant system into an initialization state. All but one of the redundant oscillators are disciplined to a time-and-frequency external input into normal disciplining state with the remaining one of the redundant oscillators in a holdover state. When all but one of the redundant oscillators have reached the normal disciplining state, placing all but one of the redundant oscillators into the holdover state, disciplining the remaining one of the redundant oscillators to the time and frequency external input, and disciplining the cascaded oscillator to one of the all but one of the redundant oscillators now in the holdover state. When the remaining one of the redundant oscillators and the cascaded oscillator have reached the normal disciplining state, transitioning from an initialization stage to a steady state management stage.

Claims (86)

1. A spoofing resistant reference time source system comprising:

an oscillator system comprising three or more redundant oscillators and a cascaded oscillator coupled to a switching system and an oscillator management computing device;

the oscillator management computing device comprising a memory coupled to a processor which is configured to execute programmed instructions stored in the memory to:

enter the three or more redundant oscillators and the cascaded oscillator into an initialization state:

discipline all but one of the redundant oscillators to a time and frequency external input into normal disciplining steady state with the remaining one of the redundant oscillators in a holdover state;

when the all but one of the redundant oscillators have reached the normal disciplining steady state, place the all but one of the redundant oscillators into the holdover state, discipline the remaining one of the redundant oscillators to the time and frequency external input, and discipline the cascaded oscillator to one of the all but one of the redundant oscillators now in the holdover state; and

when the remaining one of the redundant oscillators and the cascaded oscillator have reached the normal disciplining steady state, transition from an initialization stage to a steady state management stage.

2. The system as set forth in claim 1 further comprising executable code which when executed by a processor causes the processor to:

during the initialization state, monitor one or more metrics during the discipline of the all but one of the redundant oscillators and the one or more time and frequency external inputs coupled through one or more input components for a disciplining issue;

identify the disciplining issue based on an analysis of the one or more metrics:

disable any of the all but one of the redundant oscillators or the one or more time and frequency external inputs associated with the identified disciplining issue; and

transition to a degraded state when all of the all but one of the redundant oscillators or all of the one or more time and frequency external inputs are in the degraded state.

3. The system as set forth in claim 1 further comprising executable code which when executed by a processor causes the processor to:

enter three or more redundant oscillators and the cascaded oscillator into a steady state management stage comprising instructions to:

discipline all but one of the redundant oscillators to a time and frequency external input setting the cascaded oscillator to discipline to the remaining one of the redundant oscillators in the holdover state; and

output time and frequency external outputs coupled to the cascaded oscillator;

during the steady state management stage, monitor one or more metrics during the discipline of the all but one of the redundant oscillators and the one or more time and frequency external inputs coupled through one or more input components for a disciplining issue;

identify the disciplining issue based on an analysis of the one or more metrics;

disable any of the all but one of the redundant oscillators or the one or more time and frequency external inputs associated with the identified disciplining issue; and

transition to a degraded state when all of the all but one of the redundant oscillators or all of the one or more time and frequency external inputs are in the degraded state.

4. The system as set forth in claim 1 further comprising executable code which when executed by a processor causes the processor to:

periodically rotate which of the redundant oscillators to set to the holdover state and is set to discipline the cascaded oscillator.

5. The system as set forth in claim 1 wherein further comprising executable code which when executed by a processor when the degraded state is entered, causes the processor to:

enter the three or more redundant oscillators and the cascaded oscillator into the degraded state, wherein when the degraded state is entered:

monitor one or more metrics during the discipline of the all but one of the redundant oscillators and the one or more time and frequency external inputs coupled through one or more input components for a disciplining issue;

identify the disciplining issue based on an analysis of the monitor of the one or more metrics;

disable any of the all but one of the redundant oscillators or the one or more time and frequency external inputs with the identified disciplining issue;

enable any of the all but one of the redundant oscillators or the one or more time and frequency external inputs without the identified disciplining issue; and

exit the degraded state back to the initialization stage or a steady state management stage after a period of time when none of the redundant oscillators or the one or more time and frequency external inputs have the identified disciplining issue.

6. The system as set forth in claim 1 wherein the identified disciplining issue further comprises detected spoofing or a detected fault.

7. A non-transitory computer readable medium having stored thereon instructions comprising executable code which when executed by at least one processor, cause the processor to:

enter three or more redundant oscillators and a cascaded oscillator of a spoofing resistant reference time source system into an initialization state:

discipline all but one of the redundant oscillators to a time and frequency external input into normal disciplining steady state with the remaining one of the redundant oscillators in a holdover state;

when the all but one of the redundant oscillators have reached the normal disciplining steady state, place the all but one of the redundant oscillators into the holdover state, discipline the remaining one of the redundant oscillators to the time and frequency external input, and discipline the cascaded oscillator to one of the all but one of the redundant oscillators now in the holdover state; and

when the remaining one of the redundant oscillators and the cascaded oscillator have reached the normal disciplining steady state, transition from an initialization stage to a steady state management stage.

8. The medium as set forth in claim 7 further comprising executable code which when executed by a processor causes the processor to:

during the initialization state, monitor one or more metrics during the discipline of the all but one of the redundant oscillators and the one or more time and frequency external inputs coupled through one or more input components for a disciplining issue;

identify the disciplining issue based on an analysis of the one or more metrics:

disable any of the all but one of the redundant oscillators or the one or more time and frequency external inputs associated with the identified disciplining issue; and

transition to a degraded state when all of the all but one of the redundant oscillators or all of the one or more time and frequency external inputs are in the degraded state.

9. The medium as set forth in claim 7 further comprising executable code which when executed by a processor causes the processor to:

enter three or more redundant oscillators and the cascaded oscillator into a steady state management stage comprising instructions to:

discipline all but one of the redundant oscillators to a time and frequency external input setting the cascaded oscillator to discipline to the remaining one of the redundant oscillators in the holdover state; and

output time and frequency external outputs coupled to the cascaded oscillator;

during the steady state management stage, monitor one or more metrics during the discipline of the all but one of the redundant oscillators and the one or more time and frequency external inputs coupled through one or more input components for a disciplining issue;

identify the disciplining issue based on an analysis of the one or more metrics;

disable any of the all but one of the redundant oscillators or the one or more time and frequency external inputs associated with the identified disciplining issue; and

transition to a degraded state when all of the all but one of the redundant oscillators or all of the one or more time and frequency external inputs are in the degraded state.

10. The medium as set forth in claim 7 further comprising executable code which when executed by a processor causes the processor to:

periodically rotate which of the redundant oscillators to set to the holdover state and is set to discipline the cascaded oscillator.

11. The medium as set forth in claim 7 further comprising executable code which when executed by a processor, when the degraded state is entered, causes the processor to:

enter the three or more redundant oscillators and the cascaded oscillator into the degraded state, wherein when the degraded state is entered:

monitor one or more metrics during the discipline of the all but one of the redundant oscillators and the one or more time and frequency external inputs coupled through one or more input components for a disciplining issue;

identify the disciplining issue based on an analysis of the monitor of the one or more metrics;

disable any of the all but one of the redundant oscillators or the one or more time and frequency external inputs with the identified disciplining issue;

enable any of the all but one of the redundant oscillators or the one or more time and frequency external inputs without the identified disciplining issue; and

exit the degraded state back to the initialization stage or a steady state management stage after a period of time when none of the redundant oscillators or the one or more time and frequency external inputs have the identified disciplining issue.

12. The medium as set forth in claim 7 wherein the identified disciplining issue further comprises detected spoofing or a detected fault.

13. A method comprising:

entering, by a computing device, three or more redundant oscillators and a cascaded oscillator of a spoofing resistant reference time source system into an initialization state:

disciplining, by the computing device, all but one of the redundant oscillators to a time and frequency external input into normal disciplining steady state with the remaining one of the redundant oscillators in a holdover state;

when all but one of the redundant oscillators have reached the normal disciplining steady state, placing, by the computing device, the all but one of the redundant oscillators into the holdover state, disciplining the remaining one of the redundant oscillators to the time and frequency external input, and disciplining the cascaded oscillator to one of the all but one of the redundant oscillators now in the holdover state; and

when the remaining one of the redundant oscillators and the cascaded oscillator have reached the normal disciplining steady state, transitioning, by the computing device, from an initialization stage to a steady state management stage.

14. The method of claim 13 further comprising:

during the initialization state, monitoring, by the computing device, one or more metrics during the discipline of the all but one of the redundant oscillators and the one or more time and frequency external inputs coupled through one or more input components for a disciplining issue; and

identifying, by the computing device, the disciplining issue based on an analysis of the one or more metrics;

disabling, by the computing device, any of the all but one of the redundant oscillators or the one or more time and frequency external inputs associated with the identified disciplining issue; and

transitioning, by the computing device, to a degraded state when all of the all but one of the redundant oscillators or all of the one or more time and frequency external inputs are in the degraded state.

15. The method of claim 13 further comprising:

entering, by the computing device, three or more redundant oscillators and the cascaded oscillator into a steady state management stage comprising:

disciplining all but one of the redundant oscillators to a time and frequency external input setting the cascaded oscillator to discipline to the remaining one of the redundant oscillators in the holdover state; and

outputting time and frequency external outputs coupled to the cascaded oscillator;

during the steady state management stage, monitoring, by the computing device, one or more metrics during the discipline of the all but one of the redundant oscillators and the one or more time and frequency external inputs coupled through one or more input components for a disciplining issue;

identifying, by the computing device, the disciplining issue based on an analysis of the one or more metrics;

disabling, by the computing device, any of the all but one of the redundant oscillators or the one or more time and frequency external inputs associated with the identified disciplining issue; and

transitioning, by the computing device, to a degraded state when all of the all but one of the redundant oscillators or all of the one or more time and frequency external inputs are in the degraded state.

16. The method of claim 13 further comprising:

periodically rotating, by the computing device, which of the redundant oscillators to set to the holdover state and is set to discipline the cascaded oscillator.

17. The method of claim 13 further comprising:

entering, by the computing device, the three or more redundant oscillators and the cascaded oscillator into a degraded state, wherein when the degraded state is entered:

monitoring one or more metrics during the discipline of the all but one of the redundant oscillators and the one or more time and frequency external inputs coupled through one or more input components for a disciplining issue;

identifying the disciplining issue based on an analysis of the monitor of the one or more metrics;

disabling any of the all but one of the redundant oscillators or the one or more time and frequency external inputs with the identified disciplining issue;

enabling any of the all but one of the redundant oscillators or the one or more time and frequency external inputs without the identified disciplining issue; and

exiting the degraded state back to the initialization stage or a steady state management stage after a period of time when none of the redundant oscillators or the one or more time and frequency external inputs have the identified disciplining issue.

18. The method of claim 13 wherein the identified disciplining issue further comprises detected spoofing or a detected fault.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 28, 2022
From: SOHN, DAVID; FISCHER, JOHN; LORENTZ, MATTHIAS
To: OROLIA USA INC.
Reel/Frame 061582/0040 →
Continuity (2)
Continuation In Part 17374465 · Jul 13, 2021
Related Publication 20230046689A1 · Feb 16, 2023
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US 12,461,248 US 12,750,062