US3586776A
Expired / Lapsed
US
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Digital communication synchronization system including synchronization signal termination recognition means
Assignee: Motorola Solutions Inc
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Filing: 1969-04-16
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Granted: 1971-06-22
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Expires: 1989-04-16
Abstract
Abstract A shift register in a receiving unit uses a feedback to develop a digital code and the digital code is compared with an incoming digital code used to synchronize a digital communication signal. Initially the shift register is fed the incoming digital code signal. If the received and generated signals are in agreement an output signal is added in an integrator for each agreement. If the signals do not agree the output signal is subtracted from the signal stored in the integrator. When the signal stored in the integrator reaches a predetermined level a switching action occurs which connects the feedback output of the shift register to the input of the shift register so that the code is selfgenerating and errors in the incoming code will not be coupled into the shift register.
Inventors
- 👤 Roger F Salava
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:46
CPC Classifications
H; H04; H04L; H04L7/00; H04L7/04; H04L7/041; H04L7/043
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
202 words
A system for digital communications synchronization, including in combination, transmission means for developing a first digital synchronizing signal and transmitting the same, receiver means for receiving said first digital synchronizing signal, said receiver means including, code generation means for developing a second digital synchronizing signal, comparing means coupled to said code generation means and adapted to receive said first and second digital-synchronizing signal, said comparing means being responsive to said first and second digital synchronizing signals to develop a first output signal with said first and second digital synchronizing signals being the same, and a second output signal with said first and second digital synchronizing signals being different, adding means coupled to said comparing means for adding said first output signals and subtracting said second output signals from the added signals to develop a first control signal, magnitude detection means coupled to said adding means and responsive to said first control signal greater than a predetermined magnitude to develop a synchronization control signal, and output AND gate means coupled to said code generation means and said magnitude detection means and responsive to said synchronization control signal and a particular portion of said second digital synchronizing signal to develop a synchronization start signal.
Claim 2
Independent Claim
202 words
A system for digital communications synchronization, including in combination, transmission means for developing a first digital synchronizing signal and transmitting the same, receiver means for receiving said first digital synchronizing signal, said receiver means including, code generation means for developing a second digital synchronizing signal, comparing means coupled to said code generation means and adapted to receive said first and second digital-synchronizing signal, said comparing means being responsive to said first and second digital synchronizing signals to develop a first output signal with said first and second digital synchronizing signals being the same, and a second output signal with said first and second digital synchronizing signals being different, adding means coupled to said comparing means for adding said first output signals and subtracting said second output signals from the added signals to develop a first control signal, magnitude detection means coupled to said adding means and responsive to said first control signal greater than a predetermined magnitude to develop a synchronization control signal, and output AND gate means coupled to said code generation means and said magnitude detection means and responsive to said synchronization control signal and a particular portion of said second digital synchronizing signal to develop a synchronization start signal.
Claim 3
Dependent Claim
179 words
The digital communication synchronization system of claim 1 wherein, said transmission means includes first shift register means having a plurality of stages and an input stage, said code generation means includes second shift register means having a plurality of stages equal in number to said plurality of stages in said first shift register means and an input stage, first combining means coupled to at least two said stages of said first shift register means and responsive to the data stored therein to develop said first digital-synchronizing signal, said first combining means further being coupled to said input stage of said first shift register means for applying said first digital synchronizing signal thereto, second combining means coupled to the same stages of said second shift register means as said first combining means is coupled to said first shift register means, said second combining means being responsive to the data stored in the stages coupled thereto to develop said second digital synchronizing signal, and means coupling said second combining means to said comparing means for applying said second digital-synchronizing signal thereto.
Claim 4
Dependent Claim
89 words
The digital communication synchronization of claim 2 wherein, said receiver means further includes switch means coupled to said second combining means and said magnitude detection means, said switch means normally coupling said first digital synchronizing signal to said input stage of said second shift register means and blocking said second digital synchronizing signal therefrom, said switch means further being responsive to said synchronization control signal to couple said second digital synchronizing signal to said input stage of said second shift register means and block said first digital-synchronizing signal therefrom.
Claim 5
Dependent Claim
15 words
The digital communication synchronization system of claim 2 wherein, said adding means is an integrator.
Claim 6
Dependent Claim
77 words
The digital communication synchronization system of claim 4, wherein said output AND gate means is coupled to said magnitude detection means and separately to each of said plurality of stages of said second shift register means, said output AND gate means being responsive to a particular portion of said second digital-synchronizing signal stored in each of said plurality of stages of said second shift register means and said synchronization control signal to develop a synchronization start signal.
Claim 7
Independent Claim
213 words
A system for synchronizing a communications system with a transmitted digital-synchronizing signal, including in combination, shift register means having a plurality of stages and an input stage, combining means coupled to at least two of said plurality of stages and to said input stage, said combining means being responsive to the data stored in said stages coupled thereto to develop a local digital-synchronizing signal, comparing means adapted to receive the transmitted digital-synchronizing signal and coupled to said combining means, said comparing means being responsive to the transmitted digital-synchronizing signal and said local digital-synchronizing signal to develop a first output signal wit the local and transmitted digital-synchronizing signals being the same and a second output signal with the local and transmitted digital-synchronizing signals being different, integrating means for adding said first output signals and subtracting said second output signals from said added signals to develop a first control signal magnitude detection means coupled to said adding means and responsive to said first control signal greater than a predetermined magnitude to develop a synchronization control signal, and output AND gate means coupled to said shift register means and to said magnitude detection means and responsive to said synchronization control signal and particular data stored in said shift register means to develop a synchronization start signal.
Claim 8
Independent Claim
213 words
A system for synchronizing a communications system with a transmitted digital-synchronizing signal, including in combination, shift register means having a plurality of stages and an input stage, combining means coupled to at least two of said plurality of stages and to said input stage, said combining means being responsive to the data stored in said stages coupled thereto to develop a local digital-synchronizing signal, comparing means adapted to receive the transmitted digital-synchronizing signal and coupled to said combining means, said comparing means being responsive to the transmitted digital-synchronizing signal and said local digital-synchronizing signal to develop a first output signal wit the local and transmitted digital-synchronizing signals being the same and a second output signal with the local and transmitted digital-synchronizing signals being different, integrating means for adding said first output signals and subtracting said second output signals from said added signals to develop a first control signal magnitude detection means coupled to said adding means and responsive to said first control signal greater than a predetermined magnitude to develop a synchronization control signal, and output AND gate means coupled to said shift register means and to said magnitude detection means and responsive to said synchronization control signal and particular data stored in said shift register means to develop a synchronization start signal.
Claim 9
Dependent Claim
76 words
The digital communication synchronization system of claim 6, further including switch means coupling said combining means to said input stage and further coupled to said magnitude detection means, said switch means normally coupling said transmitted digital-synchronizing signal to said input stage and blocking said local digital-synchronizing signal therefrom, said switch means further being responsive to said synchronization control signal to couple said local digital-synchronizing signal to said input stage and block said transmitted digital-synchronizing signal therefrom.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-21 | 1974-12-21 | 1975-06-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-21 | 1978-12-21 | 1979-06-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-21 | 1982-12-21 | 1983-06-22 | $7700.00 | Window Closed / Lapsed |