Dynamic resource allocation method and apparatus for broadband services in a wireless communications system

• US 6,262,980 B1
• Filed: 12/02/1997
• Issued: 07/17/2001
• Est. Priority Date: 12/02/1997
• Status: Expired due to Term

• Current Assignee: AT&T Corporation (AT&T, Inc.)
• Original Assignee: AT&T Corporation (AT&T, Inc.)
• Inventors: Srivastava, Arty, Leung, Kin K.
• Primary Examiner(s): Pham, Chi H.
• Assistant Examiner(s): Pham, Brenda H.
• Application Number:
  US08/982,510
• Time in Patent Office: 1,323 Days
• Field of Search: 370/252, 370/336, 370/337, 370/347, 370/329, 370/436, 370/350, 455/63, 375/296, 375/135
• US Class Current: 370/336
• CPC Class Codes: H04L 41/0896 Bandwidth or capacity management, i.e. automatically increasing or decreasing capacities flow or congestion control using dynamic resource allocation, e.g. in-call renegotiation, H04L47/76
• CPC Class Codes: H04L 41/32 Specific management aspects for broadband networks
• CPC Class Codes: H04W 72/044 based on the type of the allocated resource
• CPC Class Codes: H04W 72/1215 for collaboration of different radio technologies
• CPC Class Codes: H04W 72/542 using measured or perceived quality

Abstract

A dynamic resource allocation method and apparatus for broadband services in a wireless communications system. The communications system can have a number of cells, each of which has multiple sectors. Each sector can contain a number of communications sites. Information is transmitted in time subframes scheduled to avoid interference between the sectors and cells, and different degrees of concurrent packet transmission can be scheduled for different classes of communications sites. The communications sites can be classified based on reception quality, such as by comparing their measured signal-to-interference ratio (SIR) with a SIR threshold.

Claims

1. A method for operating a communications system having a plurality of communications sites and a service area divided into a plurality of sectors, the communications system using a plurality of time subframes scheduled to avoid interference between the plurality of sectors, each subframe being further divided into a plurality of mini-frames, comprising the steps of:

scheduling a first degree of concurrent packet transmissions in a first mini-frame for a first class of communications sites located within each sector;

scheduling a second degree of concurrent packet transmissions in a second mini-frame for a second class of communications sites located within each sector, the second degree being different from the first degree; and

communicating said packets according to said scheduling.

2. The method of claim 1, further comprising the step of:

classifying the plurality of communications sites into a plurality of classes including the first class and the second class.

3. The method of claim 2, wherein said step of classifying classifies a communications site based on the reception quality of the communications site.

4. The method of claim 3, wherein said step of classifying classifies a communications site based on the signal to interference ratio of the communications site and at least one threshold signal to interference ratio.

5. The method of claim 4, wherein said step of classifying assigns a communications site to the classification having the highest degree of concurrent packet transmission possible and yet maintain a threshold success probability for the threshold signal to interference ratio.

6. The method of claim 5, wherein the threshold success probability is one.

7. The method of claim 2, wherein said step of classifying is performed at the beginning of the operation of the communications system.

8. The method of claim 2, wherein said step of classifying is performed periodically during the operation of the communications system.

9. The method of claim 2, wherein mini-frames in a subframe have different sizes.

10. The method of claim 9, wherein mini-frames are assigned a size selected based on the expected traffic from the associated class of communications sites.

11. The method of claim 9, wherein mini-frames are assigned a size selected based on the number of communications sites in the associated class.

12. The method of claim 1, wherein packet transmissions for one class of communications sites can be transmitted in an alternate mini-frame associated with another class of communications sites having a lower degree of concurrent transmission.

13. The method of claim 12, wherein packet transmissions for the one class of communications sites are transmitted in the alternate mini-frame whenever the alternate mini-frame is not being used to capacity.

14. The method of claim 2, further comprising the step of:

selecting an appropriate sector for a communications site based on the classification of the communications site in a plurality of different sectors.

15. The method of claim 1, wherein said scheduling steps create an excess information transmission schedule indicating when excess information for an initial subframe is to be transmitted in other subframes and mini-frames.

16. The method described in claim 15, wherein said other subframes are selected according to a special order.

17. The method described in claim 16, wherein said special order is created by ordering all subframes from a minimum level of interference to a maximum level of interference.

18. The method described in claim 17, wherein said special order is created using a staggered resource allocation protocol.

19. The method described in claim 18, wherein the service area has a plurality of cells, and each cell has six sectors.

20. The method described in claim 19, wherein the system has six subframes, with each sector within a cell being assigned a different subframe.

21. The method described in claim 20, wherein the pattern is created by rotating each cell 120 degrees.

22. The method described in claim 21, wherein said initial subframe for sector one is subframe one, and said special order comprises subframes four, five, three, two and six.

23. The method described in claim 22, wherein when said initial subframe is subframes two through six, said staggered resource allocation protocol staggers said special order by one subframe, respectively.

24. The method of claim 23, wherein said communications sites are divided into six classes, each of the six classes corresponding to one of the six subframes.

25. The method of claim 1, wherein the communication sites are fixed.

26. A communications system having a plurality of communications sites and a service area divided into a plurality of sectors, the communications system using a plurality of time subframes scheduled to avoid interference between the plurality of sectors, comprising:

a first class of communications units operably associated with the service area for communicating between the communications sites using at least one time subframe;

a second class of communications units operably associated with the service area for communicating between the communications sites using at least one time subframe;

a scheduler for scheduling a first degree of concurrent packet communications for the first class of communications sites and scheduling a second degree of concurrent packet communications for the second class of communications sites, the second degree being different from the first degree.

27. The system described in claim 26, wherein said scheduler creates an excess information transmission schedule.

28. The system described in claim 27, wherein said excess information transmission schedule indicates when excess information for an initial subframe is to be transmitted in other subframes.

29. The system described in claim 28, wherein said other subframes are selected according to a special order.

30. The system described in claim 29, wherein said special order is created by ordering all subframes from a minimum level of interference to a maximum level of interference.

31. The system described in claim 30, wherein said special order is created using a staggered resource allocation protocol.

32. The system described in claim 31, wherein the service area has a plurality of cells, and each cell has six sectors.

33. The system described in claim 32, wherein the system has six subframes, with each sector within a cell using a different subframe.

34. The system described in claim 33, wherein the pattern is created by rotating each cell 120 degrees.

35. The system described in claim 34, wherein said initial subframe for sector one is subframe one, and said special order comprises subframes four, five, three, two and six.

36. The system described in claim 35, wherein when said initial subframe is subframes two through six and the staggered resource allocation protocol staggers said special order by one subframe.