US5889765A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Bi-directional communications network
Assignee: RPX Clearinghouse LLC
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Filing: 1997-02-11
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Granted: 1999-03-30
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Expires: 2017-02-11
Abstract
Abstract A bi-directional communications network is disclosed, and in particular a TDM/TDMA protocol for the shared coax medium downstream/upstream resource. This protocol provides a very efficient technique for resource sharing in the access network of HFC systems. A method of communicating information between a central station and a plurality of terminals in a distribution network, is also disclosed. This invention allows the ranging of the terminals of unknown distance from the central station within an upstream ATM cell slot dynamically allocated for the marshalling process by the central station.
Inventors
- 👤 Graeme Gibbs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:23
CPC Classifications
H; H04; H04J; H04J3/00; H04J3/02; H04J3/06; H04J3/0635; H04J3/0682; H04J3/16; H04J3/1694; H04N; H04N7/00; H04N7/16; H04N7/173; H04N7/17309; H04Q; H04Q11/00; H04Q11/04; H04Q11/0428; H04Q11/0478; H04J2203/00; H04J2203/0001; H04J2203/0003; H04J2203/0012; H04L; H04L12/00; H04L12/54; H04L12/56; H04L12/5601; H04L2012/5603; H04L2012/5604; H04L2012/5605; H04L2012/5606; H04L2012/5609; H04L2012/561; H04L2012/5614; H04L2012/5615; H04L2012/5616
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
66 words
An ATM-TDMA system, wherein upstream ATM cell slots are dynamically allocated, wherein marshalling is achieved within an upstream cell slot according to the inequality: td+(Im/b)<(Is/b) where: td is the maximum differential round-trip delay; Im is the minimum length (in bits) of the marshalling sequence necessary to allow correct marshalling; b is bit rate of upstream traffic; Is is the length of cell slot minus guard band.
Claim 2
Dependent Claim
66 words
An ATM-TDMA system, wherein upstream ATM cell slots are dynamically allocated, wherein marshalling is achieved within an upstream cell slot according to the inequality: td+(Im/b)<(Is/b) where: td is the maximum differential round-trip delay; Im is the minimum length (in bits) of the marshalling sequence necessary to allow correct marshalling; b is bit rate of upstream traffic; Is is the length of cell slot minus guard band.
Claim 3
Dependent Claim
41 words
A system according to claim 1, wherein the basestation has control over the timing of cell slot allocation and the timing of marshalling responses, whereby the slot to be used for marshalling is removed from the cell allocation mechanism during marshalling.
Claim 4
Independent Claim
123 words
A method of communicating information between a central station and a plurality of terminals in a distribution network, the method comprising the steps of: at the central station, determining downstream TDM frames, for transmission of distribution information and overhead information from the central station to the plurality of terminals, and upstream TDMA frames, for transmission of information in respective time slots from the terminals to the central station, wherein marshalling is achieved within an upstream cell slot according to the inequality: td+(Im/b)<(Is/b) where: td is the maximum differential round-trip delay; Im is the minimum length (in bits) of the marshalling sequence necessary to allow correct marshalling; b is bit rate of upstream traffic; Is is the length of cell slot minus guard band.
Claim 5
Independent Claim
123 words
A method of communicating information between a central station and a plurality of terminals in a distribution network, the method comprising the steps of: at the central station, determining downstream TDM frames, for transmission of distribution information and overhead information from the central station to the plurality of terminals, and upstream TDMA frames, for transmission of information in respective time slots from the terminals to the central station, wherein marshalling is achieved within an upstream cell slot according to the inequality: td+(Im/b)<(Is/b) where: td is the maximum differential round-trip delay; Im is the minimum length (in bits) of the marshalling sequence necessary to allow correct marshalling; b is bit rate of upstream traffic; Is is the length of cell slot minus guard band.
Claim 6
Dependent Claim
51 words
A method according to claim 3, wherein the timing of cell slot allocation and the timing of marshalling responses is controlled by the central station, whereby the slot to be used for marshalling is removed from the cell allocation mechanism for the time during which a marshalling response has been commanded.
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) | 2002-03-29 | 2002-09-28 | 2003-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-03-29 | 2006-09-28 | 2007-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-03-29 | 2010-09-28 | 2011-03-30 | $7700.00 | Window Closed / Lapsed |