Method and apparatus for bandwidth reuse in a communication network

• US 5,963,561 A
• Filed: 12/05/1996
• Issued: 10/05/1999
• Est. Priority Date: 12/05/1996
• Status: Expired due to Term

• Current Assignee: AT&T Corporation (AT&T, Inc.)
• Original Assignee: AT&T Corporation (AT&T, Inc.)
• Inventors: Lu, Xiaolin
• Primary Examiner(s): Marcelo, Melvin
• Assistant Examiner(s): KWOH, JASPER C
• Application Number:
  US08/760,790
• Time in Patent Office: 1,034 Days
• Field of Search: 370/319, 370/343, 370/330, 370/480, 370/276, 370/280, 370/281, 370/481, 370/482, 370/484, 370/436, 370/293-295, 370/478, 370/458, 370/498, 455/447
• US Class Current: 370/458
• CPC Class Codes: H04B 10/2589 Bidirectional transmission
• CPC Class Codes: H04J 1/08 Arrangements for combining channels branching filters H01P1/213, H03H7/46
• CPC Class Codes: H04J 1/10 Intermediate station arrangements, e.g. for branching, for tapping-off repeater circuits H04B3/36, H04B3/58; two-way amplifiers H03F3/62
• CPC Class Codes: H04J 3/02 Details electronic switching or gating H03K17/00

Abstract

A method and apparatus is provided within a system having a total bandwidth divided into multiple segments. The segments are preferably frequency segments in a frequency division multiplexing environment or time slot segments in a time division multiplexing environment. The system transmits first downstream information from a head end to a router within a first bandwidth segment and transmits second downstream information from the head end to the router within a second bandwidth segment. The router sends the first downstream information to a first destination and sends the second downstream information to a second destination. First upstream information is transmitted from the first destination and through the router to the head end within a bandwidth segment used for downstream transmission other than the first bandwidth segment. Second upstream information is transmitted from the second destination and through the router to the head end within a bandwidth segment used for downstream transmission other than the second bandwidth segment. Upstream information from a given destination is always sent over a different bandwidth from the bandwidth over which the downstream information was received. Further, the router directs respective downstream information to respective EUs while blocking other information to maintain privacy of information.

Claims

1. A method for reusing bandwidth within a system having a total bandwidth divided into multiple segments, the total bandwidth allocated for both upstream and downstream transmission, the method comprising the steps of:

transmitting first downstream information within a first bandwidth segment;

transmitting second downstream information within a second bandwidth segment;

routing the first downstream information transmitted within the first bandwidth segment to a first destination;

routing the second downstream information transmitted within the second bandwidth segment to a second destination; and

transmitting first upstream information from the first destination within a bandwidth segment of the total bandwidth used for downstream transmission other than the first bandwidth segment.

2. The method of claim 1, further comprising the step of transmitting second upstream information from the second destination within a bandwidth segment used for downstream transmission other than the second bandwidth segment.

3. The method of claim 2, wherein the first upstream information is transmitted within the second bandwidth segment and the second upstream information is transmitted within the first bandwidth segment.

4. The method of claim 2, further comprising the steps of:

transmitting third downstream information within a third bandwidth segment;

routing the third downstream information transmitted within the third bandwidth segment to a third destination; and

transmitting third upstream information from the third destination within a bandwidth segment used for downstream transmission other than the third bandwidth segment.

5. The method of claim 4, further comprising the steps of:

transmitting fourth downstream information within a fourth bandwidth segment;

routing the fourth downstream information transmitted within the fourth bandwidth segment to a fourth destination; and

transmitting fourth upstream information from the fourth destination within a bandwidth segment used for downstream transmission other than the fourth bandwidth segment.

6. The method of claim 2, wherein the total bandwidth comprises a frequency range.

7. The method of claim 6, further comprising the steps of:

routing the first downstream and upstream information through a first filter set; and

routing the second downstream and upstream information through a second filter set.

8. The method of claim 7, wherein the first and second filter set comprise dual-bandpass filters.

9. The method of claim 7, wherein the first and second filter sets comprise diplexers, low pass filters and high pass filters.

10. The method of claim 2, wherein:

the first downstream information and second downstream information are transmitted from a head end along a first transmission medium; and

the first upstream information and second upstream information are received by the head end along a second transmission medium.

11. The method of claim 10, wherein the first downstream information routing step comprises routing the first downstream information from the first transmission medium via a third transmission medium to the first destination, the first upstream information transmitting step comprising transmitting the first upstream information from the first destination via the third transmission medium to the second transmission medium.

12. The method of claim 11, wherein the second downstream information routing step comprises routing the second downstream information from the first transmission medium via a fourth transmission medium to the second destination, the second upstream information transmitting step comprises transmitting the second upstream information from the second destination via the fourth transmission medium to the second transmission medium.

13. The method of claim 2, wherein the total bandwidth comprises a time span.

14. The method of claim 13, further comprising the steps of:

routing the first downstream and upstream information through a first clocked switch; and

routing the second downstream and upstream information through a second clocked switch.

15. The method of claim 13, wherein the first downstream information routing step comprises routing the first downstream information in a remote node from a first transmission medium to the first destination based on a clocked switch, and the second downstream information routing step comprises routing the second downstream information in the remote node from the first transmission medium to the second destination based on the clocked switch.

16. The method of claim 15, wherein the first upstream transmitting step comprises transmitting the first upstream information from the first destination to a second transmission medium based on the clocked switch, and the second upstream information transmitting step comprises transmitting the second upstream information from the second destination to the second transmission medium based on the clocked switch.

17. The method of claim 2, wherein the first downstream information, the second downstream information, the first upstream information and the second upstream information are coded information.

18. A system for reusing bandwidth, the system having a total bandwidth divided into multiple segments, the total bandwidth allocated for both upstream and downstream transmission, the system comprising:

a head end that transmits first downstream information within a first bandwidth segment and transmits second downstream information within a second bandwidth segment; and

a router that routes the first downstream information transmitted within the first bandwidth segment to a first destination and routes the second downstream information transmitted within the second bandwidth segment to a second destination, and routes first upstream information originating from the first destination to the head end within a bandwidth segment of the total bandwidth used for downstream transmission other than the first bandwidth segment.

19. The system of claim 18, wherein the router routes second upstream information originating from the second destination to the head end within a bandwidth segment used for downstream transmission other than the second bandwidth segment.

20. The system of claim 19, wherein the first upstream information is transmitted within the second bandwidth segment and the second upstream information is transmitted within the first bandwidth segment.

21. The system of claim 19, wherein the total bandwidth comprises a frequency range.

22. The system of claim 21, wherein the router comprises a first filter set that routes the first downstream information to the first destination and its upstream information to the head end and a second filter set that routes the second downstream information to the second destination and its upstream information to the head end.

23. The system of claim 22, wherein the first and second filter sets comprise dual-bandpass filters.

24. The system of claim 22, wherein the first and second filter sets comprise diplexers, low pass filters and high pass filters.

25. The system of claim 19, wherein the head end transmits the first downstream information and the second downstream information from the head end along a first transmission medium;

and

the first upstream information and the second upstream information are received by the head end along a second transmission medium.

26. The system of claim 25, wherein:

said first downstream information is routed from the first transmission medium via a third transmission medium to the first destination; and

the first upstream information is transmitted from the first destination via the third transmission medium to the second transmission medium.

27. The system of claim 26, wherein:

the second downstream information is routed from the first transmission medium via a fourth transmission medium to the second destination; and

said second upstream information is transmitted from the second destination via said fourth transmission medium to the second transmission medium.

28. The system of claim 19, wherein the total bandwidth comprises a time span.

29. The system of claim 18, further comprising a first clocked switch that routes the first downstream information to the first destination and a second clocked switch that routes the second downstream information to the second destination.

30. A method for reusing bandwidth in a communication system comprising the steps of:

transmitting downstream information from a node to a first destination within a first bandwidth segment;

transmitting downstream information from said node to at least one other destination within a corresponding at least one other bandwidth segment; and

transmitting upstream information from said first destination to said node within one of said at least one other bandwidth segment.

31. The method of claim 30, wherein said bandwidth segments are frequency segments.

32. The method of claim 31, wherein said first bandwidth segment and said one of said at least one other bandwidth segment are separated by one frequency segment.

33. The method of claim 30, wherein said bandwidth segments are time slot segments.

34. The method of claim 33, wherein said first bandwidth segment and said one of said at least one other bandwidth segment are separated by one time slot.

35. The method of claim 30, wherein said downstream information is transmitted at least in part over a shared transmission medium.

36. The method of claim 30, wherein said upstream information is transmitted at least in part over a shared transmission medium.