US4748616A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and arrangement for transmitting and extracting a timing signal
Assignee: NEC Corp
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Filing: 1986-05-20
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Granted: 1988-05-31
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Expires: 2006-05-20
Abstract
Abstract A method for transmitting and extracting a timing signal for use in a multi-carrier parallel data transmission system having the carrier frequencies of channels arranged at baud rate intervals. On a transmitting side, two pilot signals, whose frequency difference is an integral multiple of the baud rate, are inserted outside the signal band of said data transmission system and transmitted to a receiving side. On the receiving side, the frequency difference signal of said two pilot signals is taken out and is frequency-divided to extract a timing signal equal to the baud rate frequency. By this use of two pilot signals, it then becomes possible to transmit and extract a timing signal without sacrificing any of the valuable carriers contained within the data transmission band.
Inventors
- 👤 Osamu Tanaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:43
CPC Classifications
H; H04; H04L; H04L27/00; H04L27/26; H04L27/2601; H04L27/2602; H04L27/261; H04L27/2613; H04L27/2626; H04L27/2647; H04L27/2655; H04L27/2662; H04L27/2668; H04L27/2673; H04L27/2675; H04L27/2657
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
184 words
A method for transmitting and extracting a timing signal for use in a multi-carrier parallel data transmission system having the carrier frequencies of channels arranged at baud rate intervals, comprising the steps of: (a) transmitting two of said carriers as a first pair of pilot signals which have a first frequency difference equal to the baud rate; (b) taking out a first signal having a reference phase and a frequency equal to the first frequency difference from said first pair of pilot signals; (c) transmitting a second pair of pilot signals having a second frequency difference which is n times the baud rate; (d) taking out a second signal having a frequency equal to the second frequency difference from said second pair of pilot signals; (e) producing a third signal having any one of n possible phases and a frequency equal to the baud rate by frequency-dividing by n said second signal; and (f) extracting a timing signal having a phase, out of said n possible phases, closest to said reference phase and a frequency equal to the baud rate from said third signal.
Claim 2
Independent Claim
184 words
A method for transmitting and extracting a timing signal for use in a multi-carrier parallel data transmission system having the carrier frequencies of channels arranged at baud rate intervals, comprising the steps of: (a) transmitting two of said carriers as a first pair of pilot signals which have a first frequency difference equal to the baud rate; (b) taking out a first signal having a reference phase and a frequency equal to the first frequency difference from said first pair of pilot signals; (c) transmitting a second pair of pilot signals having a second frequency difference which is n times the baud rate; (d) taking out a second signal having a frequency equal to the second frequency difference from said second pair of pilot signals; (e) producing a third signal having any one of n possible phases and a frequency equal to the baud rate by frequency-dividing by n said second signal; and (f) extracting a timing signal having a phase, out of said n possible phases, closest to said reference phase and a frequency equal to the baud rate from said third signal.
Claim 3
Dependent Claim
204 words
Apparatus for transmitting and extracting a timing signal for use in a multi-carrier parallel data transmission system having the carrier frequencies of channels arranged at baud rate intervals, comprising: (a) means for generating a first pair of pilot signals having a first frequency difference equal to the baud rate when said transmission system is in a training mode and a second pair of pilot signals having a second frequency difference equal to n times the baud rate when said transmission system is in a data transmission mode, where n is an integer; (b) means for taking out a first signal having a reference phase and a frequency equal to the first frequency difference from said first pair of pilot signals; (c) means for taking out a second signal indicative of the second frequency difference from said second pair of pilot signals; (d) means for producing a third signal having any one of n possible phases and a frequency equal to the baud rate by frequency-dividing by n said second signal; and (e) means for extracting a timing signal having a phase out of said n possible phases, closest to said reference phase and a frequency equal to the baud rate from said third signal.
Claim 4
Dependent Claim
204 words
Apparatus for transmitting and extracting a timing signal for use in a multi-carrier parallel data transmission system having the carrier frequencies of channels arranged at baud rate intervals, comprising: (a) means for generating a first pair of pilot signals having a first frequency difference equal to the baud rate when said transmission system is in a training mode and a second pair of pilot signals having a second frequency difference equal to n times the baud rate when said transmission system is in a data transmission mode, where n is an integer; (b) means for taking out a first signal having a reference phase and a frequency equal to the first frequency difference from said first pair of pilot signals; (c) means for taking out a second signal indicative of the second frequency difference from said second pair of pilot signals; (d) means for producing a third signal having any one of n possible phases and a frequency equal to the baud rate by frequency-dividing by n said second signal; and (e) means for extracting a timing signal having a phase out of said n possible phases, closest to said reference phase and a frequency equal to the baud rate from said third signal.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-05-31 | 1991-11-30 | 1992-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-31 | 1995-11-30 | 1996-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-31 | 1999-11-30 | 2000-05-31 | $7700.00 | Window Closed / Lapsed |