US3902014A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit arrangement for regenerating the modulation timing of a line signal in a data transmission equipment
Assignee: Telefonaktiebolaget LM Ericsson AB
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Filing: 1973-08-15
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Granted: 1975-08-26
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Expires: 1993-08-15
Abstract
Abstract A circuit arrangement in the receiver of a data transmission equipment for regenerating the modulation timing of an incoming line signal includes a detector for detecting the modulation timing of the incoming signal which is connected to a first input of a summing circuit. The output of the summing circuit is connected to the second input thereof via a controllable switch and a bandpass filter having a center frequency equal to the frequency of the modulation timing. Upon the start of the transmission the switch is in its open state and the figure of merit of the circuit is low. After a certain time the switch is closed and a feed-back loop is obtained whereby the figure of merit is increased.
Inventors
- 👤 Key Ake Lindell
- 👤 Goran Karl Arvid Pettersson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 22:33
CPC Classifications
H; H04; H04L; H04L7/00; H04L7/02; H04L7/027
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
265 words
In the receiver of a digital data transmission system, apparatus for regenerating the modulation timing of received line signals which are binarily modulated comprising: a band pass filter having an input and an output and having a center frequency generally equal to a frequency corresponding to the modulation timing; a timing signal output; means for connecting said timing signal output to the output of said band pass filter; a signal summing means having first and second inputs and an output for the analog addition of the amplitudes of the signals present at said first and second inputs; means for connecting the output of said signal summing means to the input of said band pass filter; a detector means having an input adapted to receive the line signals and an output for transmitting from the output thereof a signal representing at least one border of the envelope of a line signal received at the input thereof; means for connecting the ouTput of said detector means to the first input of said summing means; a controllable switch means having a signal input connected to said timing signal output, a signal output connected to the second input of said signal summing means, and a control input, said switch being open until the receipt of a signal at said control input; and a signal level detector having an input adapted to receive a line signal and an output connected to the control input of said switch, said signal level detector emitting a signal from the output thereof when the signal present at the input thereof exceeds a given amplitude.
Claim 2
Dependent Claim
265 words
In the receiver of a digital data transmission system, apparatus for regenerating the modulation timing of received line signals which are binarily modulated comprising: a band pass filter having an input and an output and having a center frequency generally equal to a frequency corresponding to the modulation timing; a timing signal output; means for connecting said timing signal output to the output of said band pass filter; a signal summing means having first and second inputs and an output for the analog addition of the amplitudes of the signals present at said first and second inputs; means for connecting the output of said signal summing means to the input of said band pass filter; a detector means having an input adapted to receive the line signals and an output for transmitting from the output thereof a signal representing at least one border of the envelope of a line signal received at the input thereof; means for connecting the ouTput of said detector means to the first input of said summing means; a controllable switch means having a signal input connected to said timing signal output, a signal output connected to the second input of said signal summing means, and a control input, said switch being open until the receipt of a signal at said control input; and a signal level detector having an input adapted to receive a line signal and an output connected to the control input of said switch, said signal level detector emitting a signal from the output thereof when the signal present at the input thereof exceeds a given amplitude.
Claim 3
Dependent Claim
27 words
The apparatus of claim 1 wherein said means for connecting the output of said band pass filter to said timing signal output comprises a signal amplitude limiter.
Claim 4
Dependent Claim
36 words
The apparatus of claim 1 wherein said signal level detector includes delay means for delaying the emission of a signal therefrom for a period of time related to the time constant of said band pass filter.
References Cited (Backward Citations)
US3057959A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-08-25 | 1979-02-24 | 1979-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-25 | 1983-02-24 | 1983-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-25 | 1987-02-24 | 1987-08-26 | $7700.00 | Window Closed / Lapsed |