US3801981A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Remote clock synchronization system
Assignee: United States Department of the Navy
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Filing: 1971-04-23
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Granted: 1974-04-02
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Expires: 1991-04-23
Abstract
Abstract A system for the precise synchronization of high frequency electronic clocks by providing each station other than the master station with a tracking circuit. The tracking circuit consists of an early gate generated just prior to the arrival of the synchronizing pulse from the master station and a late gate generated just after the synchronizing pulse is received from the master station. If the synchronizing pulse received from the master station is either late or early the clock will either speed up or slow down so that it will be in synchronization with the synchronizing pulses received from the master station.
Inventors
- 👤 F Alpers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:14
CPC Classifications
H; H03; H03L; H03L7/00; G; G04; G04R; G04R40/00
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
222 words
In a remote clock synchronizing system, the combination comprising: a. a high frequency oscillator, b. a pulse generator coupled to said oscillator for generating an output pulse for each cycle of said oscillator, c. a preset counter coupled to said pulse generator for generating an output pulse and recycling after a predetermined number of pulses are received from said pulse generator, d. an input terminal for receiving synchronizing pulses from a remotely located master station, e. a first multivibrator coupled to a preset counter for generating a first gate signal so as to commence in response to the output pulse from said preset counter and to terminate after a first predetermined time delay. f. a second multivibrator coupled to said preset counter for generating a second gate signal so as to commence immediately upon termination of said first gate signal and to terminate after a second predetermined time delay. g. gate circuit means coupled to said input terminal and to said first and second multivibrators and having an output coupled to said oscillator for gating an output signal to increase the output frequency of said oscillator when said first gate signal is in coincidence with said synchronizing pulse and an output signal to decrease the output frequency of said clock when said second gate signal is in coincidence with said synchronizing pulse.
Claim 2
Dependent Claim
222 words
In a remote clock synchronizing system, the combination comprising: a. a high frequency oscillator, b. a pulse generator coupled to said oscillator for generating an output pulse for each cycle of said oscillator, c. a preset counter coupled to said pulse generator for generating an output pulse and recycling after a predetermined number of pulses are received from said pulse generator, d. an input terminal for receiving synchronizing pulses from a remotely located master station, e. a first multivibrator coupled to a preset counter for generating a first gate signal so as to commence in response to the output pulse from said preset counter and to terminate after a first predetermined time delay. f. a second multivibrator coupled to said preset counter for generating a second gate signal so as to commence immediately upon termination of said first gate signal and to terminate after a second predetermined time delay. g. gate circuit means coupled to said input terminal and to said first and second multivibrators and having an output coupled to said oscillator for gating an output signal to increase the output frequency of said oscillator when said first gate signal is in coincidence with said synchronizing pulse and an output signal to decrease the output frequency of said clock when said second gate signal is in coincidence with said synchronizing pulse.
Claim 3
Dependent Claim
36 words
The synchronizing system of claim 1 wherein a memory circuit is coupled between said gate circuit means and said oscillator to maintain the adjusted frequency during the time interval between pulses received from said master station.
Claim 4
Dependent Claim
31 words
The synchronizing system of claim 1 wherein said second predetermined time delay is a counter circuit whose output provides the zero time pulse so that said time delay is accurately maintained.
Claim 5
Dependent Claim
75 words
The synchronizing system of claim 3 wherein said first and second multivibrators are bistable multivibrators, said first bistable multivibrator being turned on by the output pulse from said preset counter and being turned off by a first delayed signal initiated by the output pulse from said preset counter, said second bistable multivibrator being turned on by saiD first delayed signal and being turned off by a second delayed signal initiated by said first delayed signal.
Claim 6
Dependent Claim
55 words
The synchronizing system of claim 4 wherein said gate circuit means includes: a. a first gated amplifier for passing synchronizing pulses when received in coincidence with the gate signal from said first bistable multivibrator and a second gated amplifier for passing synchronizing pulses received in coincidence with the gate signal from said second bistable multivibrator.
Claim 7
Dependent Claim
65 words
The system of claim 5 wherein said master station utilizes the time of arrival of a beacon pulse from said remote station to generate a synchronization pulse such that the travel time of the master pulse to the remote station is equal to the travel time of the remote station beacon pulse plus said second time delay and varying distances between stations are automatically accommodated.
References Cited (Backward Citations)
US3250896A
Cited
US3440652A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-01 | 1977-10-01 | 1978-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-01 | 1981-10-01 | 1982-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-01 | 1985-10-01 | 1986-04-02 | $7700.00 | Window Closed / Lapsed |