US4525846A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Modem in-band secondary channel via radial modulation
Assignee: Paradyne Corp
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Filing: 1982-12-27
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Granted: 1985-06-25
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Expires: 2002-12-27
Abstract
Abstract A transmission system for transmitting a first data series, and a second data series from a first modem to a second modem using QAM or PSK type modulation techniques. The first data series is sent using standard QAM techniques such as an 8-point scheme, wherein each point has a radial component. The second data series is sent by modulating slightly the radial components of the transmitted symbols between two values in accordance with the second data series.
Inventors
- 👤 Gordon Bremer
- 👤 William L. Betts
- 👤 Robert T. Greene
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:02
CPC Classifications
H; H04; H04L; H04L27/00; H04L27/18; H04L27/20; H04L27/2032; H04L27/2053; H04L27/206; H04L27/2067; H04L27/2071; H04L27/32; H04L27/34; H04L27/345; H04L27/3461; H04L27/3472
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
162 words
A method of transmitting a first and second input series of input bits simultaneously, over a single data channel comprising: generating a series of symbols having a radial amplitude and corresponding to said first series of input bits; maintaining the radial amplitude of said symbols at a first level if said second input bits have a first value and alternating said radial amplitude between said first value and a second value for consecutive symbols when said second input bits have a second value; sending said symbols over said communication channel, to a receiver; detecting the radial amplitudes of the signals received by said receiver; correlating the radial amplitudes of a last preselected number of received signals to obtain a correlated value; comparing said correlated value to a threshold value; and generating a series of output bits having a first value if said correlated value is above said threshold value; and a second value if said correlated value is below said threshold value.
Claim 2
Independent Claim
162 words
A method of transmitting a first and second input series of input bits simultaneously, over a single data channel comprising: generating a series of symbols having a radial amplitude and corresponding to said first series of input bits; maintaining the radial amplitude of said symbols at a first level if said second input bits have a first value and alternating said radial amplitude between said first value and a second value for consecutive symbols when said second input bits have a second value; sending said symbols over said communication channel, to a receiver; detecting the radial amplitudes of the signals received by said receiver; correlating the radial amplitudes of a last preselected number of received signals to obtain a correlated value; comparing said correlated value to a threshold value; and generating a series of output bits having a first value if said correlated value is above said threshold value; and a second value if said correlated value is below said threshold value.
Claim 3
Dependent Claim
30 words
The method of claim 1 wherein said first and second series of input bits have corresponding first and second data rates, said first data rate exceeding said second data rate.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-06-24 | 1988-12-24 | 1989-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-24 | 1992-12-24 | 1993-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-24 | 1996-12-24 | 1997-06-25 | $7700.00 | Window Closed / Lapsed |