Method and system for radio-independent predictive handoffs in a wireless network

• US 7,711,372 B2
• Filed: 05/13/2005
• Issued: 05/04/2010
• Est. Priority Date: 05/13/2005
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Iyer, Jayaraman R., Oswal, Anand K.
• Primary Examiner(s): Ramakrishnaiah; Melur
• Application Number:
  US11/128,730
• Publication Number:
  US 20060258361A1
• Time in Patent Office: 1,817 Days
• Field of Search: 455/447, 455/436, 455/437, 455/438, 455/439, 455/442, 455/452.2, 455/453
• US Class Current: 455/447
• CPC Class Codes: H04W 36/16 Performing reselection for specific purposes

Abstract

According to one embodiment of the invention, a method includes determining, at a base station, at least one usability factor providing a relative measure of the desirability of receiving control of a mobile unit. The method also includes communicating, from a base station to a remote controller, the determined at least one usability factor for comparison to at least one usability factor of another base station as determined at the other base station and communicated to the remote controller. The method also includes taking control, by the base station, of the mobile unit in response to receiving a signal from a controller to take control of the mobile unit in response to comparison of the controller of the at least one usability factor determined by the base station and the at least one usability factor determined by the other base station.

Claims

1. A method for call handoff in a wireless network comprising a controller and a plurality of base stations including first and second base stations, the method comprising:

determining at the first and second base stations at least one respective usability factor, each respective usability factor providing a relative measure of the desirability of receiving control of a mobile unit;

communicating each of the at least one usability factors from each of the first and second base stations to the controller without communicating raw signal strengths from the first and second base stations to the controller, the controller located remote from the first and second base stations; and

selecting one of the first and second base stations to receive control of the mobile unit by comparing, by the controller, the at least one usability factor for the first base station to the at least one usability factor for the second base station without comparing radio signal strengths of the first and second base stations.

2. The method of claim 1, wherein the at least one usability factor includes a load of the respective base station.

3. The method of claim 1, wherein the at least one usability factor includes a cost associated with a respective base station receiving control of the mobile unit.

4. The method of claim 1, wherein the at least one usability factor includes a load of the respective base station and a cost associated with the respective base station receiving control of the mobile unit.

5. The method of claim 1, wherein the at least one usability factor includes a load of the respective base station for each respective one of a plurality of Quality of Service levels for the respective base station.

6. The method of claim 1, wherein the at least one usability factor includes the total number of mobile units a respective base station can accommodate.

7. The method of claim 1, wherein the at least one usability factor includes the number of additional mobile units a respective base station can accommodate.

8. The method of claim 1, wherein the at least one respective usability factor for the first base station is determined according to the same criteria as the at least one respective usability factor for the second base station.

9. The method of claim 1, wherein the at least one respective usability factor for the first base station is determined according to different criteria from the at least one respective usability factor for the second base station.

10. The method of claim 1, wherein the respective usability factor is determined based on an associated spectrum, quality of the associated spectrum, and an average speed of access by a user.

11. The method of claim 10, wherein the usability factor is further indicative of the instantaneous number of users that can be supported by the respective base station.

12. An apparatus comprising:

a wireless network base station, the base station operable to receive a wireless call and transmit at least portions of the call to a wired line, the base station further comprising logic encoded in a computer-readable medium that when executed on a processor is operable to;

determine at least one usability factor providing a relative measure of the desirability of receiving control of a mobile unit;

communicate the at least one usability factor to a remote controller for comparison to at least one usability factor of another base station that is determined at the other base station and communicated to the remote controller, the communication performed without communicating raw signal strengths from the base station to the controller; and

receive a signal from the controller to take control of the mobile unit in response to comparison by the controller of the at least one usability factor determined by the base station and at least one usability factor to be determined by the other base station, the comparison performed without comparing radio signal strengths of the base station and the other base station.

13. The apparatus of claim 12, wherein the at least one usability factor includes a load of the respective base station.

14. The apparatus of claim 12, wherein the at least one usability factor includes a cost associated with a respective base station receiving control of the mobile unit.

15. The apparatus of claim 12, wherein the at least one usability factor includes a load of the respective base station and a cost associated with the respective base station receiving control of the mobile unit.

16. The apparatus of claim 12, wherein the at least one usability factor includes a load of the respective base station for each respective one of a plurality of Quality of Service levels for the respective base station.

17. The apparatus of claim 12, wherein the at least one usability factor includes the total number of mobile units a respective base station can accommodate.

18. The apparatus of claim 12, wherein the at least one usability factor includes the number of additional mobile units a respective base station can accommodate.

19. The apparatus of claim 12, wherein the at least one respective usability factor for the first base station is determined according to the same criteria as the at least one respective usability factor for the second base station.

20. The apparatus of claim 12, wherein the at least one respective usability factor for the first base station is determined according to different criteria from the at least one respective usability factor for the second base station.

21. The apparatus of claim 12, wherein the respective usability factor is determined based on an associated spectrum, quality of the associated spectrum, and the average user throughput.

22. The apparatus of claim 21, wherein the usability factor is further indicative of the instantaneous number of users that can be supported by the respective base station.

23. A method implemented by a base station in a wireless network comprising:

determining, at the base station, at least one usability factor providing a relative measure of the desirability of receiving control of a mobile unit;

communicating, from the base station to a remote controller, the determined at least one usability factor for comparison to at least one usability factor of another base station that is determined at the other base station and communicated to the remote controller, the communication performed without communicating raw signal strengths from the base station to the controller; and

taking control, by the base station, of the mobile unit in response to receiving a signal from the controller to take control of the mobile unit in response to comparison by the controller of the at least one usability factor determined by the base station and the at least one usability factor determined by the other base station, the comparison performed without comparing radio signal strengths of the base station and the other base station.

24. The method of claim 23, wherein the at least one usability factor includes a load of the base station.

25. The method of claim 23, wherein the at least one usability factor includes a cost associated with the base station receiving control of the mobile unit.

26. The method of claim 23, wherein the at least one usability factor is determined based on an associated spectrum, quality of the associated spectrum, and an average user throughput.

27. An apparatus for use with a wireless network including a plurality of base stations, the apparatus comprising:

a controller operable to;

receive a first at least one usability factor from a first base station and a second at least one usability factor from a second base station, the first and second at least one usability factors each providing a relative measure of the desirability of receiving control of a mobile unit, the first and second base stations having communicated the first at least one usability factor and the second at least one usability factor, respectively, without communicating raw signal strengths from the first and second base stations to the controller;

compare the first at least one usability factor to the second at least one usability factor without comparing radio signal strengths of the first and second base stations; and

select the first or second base station to take control of the mobile unit based on the comparison.

28. The apparatus of claim 27, wherein the at least one usability factor includes a load of the respective base station.

29. The apparatus of claim 27, wherein the at least one usability factor includes a cost associated with a respective base station receiving control of the mobile unit.

30. The apparatus of claim 27, wherein the respective usability factor is determined based on an associated spectrum, quality of the associated spectrum, and an average user throughput.

31. The apparatus of claim 27, wherein the apparatus is an IP router.

32. A method implemented by a controller in a wireless network comprising:

receiving, by the controller, a first at least one usability factor from a first base station and a second at least one usability factor from a second base station, the first and second at least one usability factors each providing a relative measure of the desirability of receiving control of a mobile unit, the first and second base stations having communicated the first at least one usability factor and the second at least one usability factor, respectively, without communicating raw signal strengths from the first and second base stations to the controller;

comparing, by the controller, the first at least one usability factor to the second at least one usability factor without comparing radio signal strengths of the first and second base stations; and

selecting, by the controller, the first or second base station to take control of the mobile unit based on the comparison.

33. The method of claim 32, wherein the at least one usability factor includes a load of the respective base station.

34. The method of claim 32, wherein the at least one usability factor includes a cost associated with a respective base station receiving control of the mobile unit.

35. The method of claim 32, wherein the respective usability factor is determined based on an associated spectrum, quality of the associated spectrum, and an average user throughput.

36. The method of claim 32, wherein the controller is an IP router.

37. A wireless network comprising:

a plurality of base stations, the plurality including first and second base stations;

at least one controller;

means for determining at the first and second base stations at least one respective usability factor, each respective usability factor providing a relative measure of the desirability of receiving control of a mobile unit;

means for communicating each of the at least one usability factors from each of the first and second base stations to the controller without communicating raw signal strengths from the first and second base stations to the controller, the controller located remote from the first and second base stations; and

means for selecting one of the first and second base stations to receive control of the mobile unit by comparing, by the controller, the at least one usability factor for the first base station to the at least one usability factor for the second base station without comparing radio signal strengths of the first and second base stations.

38. The wireless network of claim 37, wherein the at least one usability factor includes a load of the respective base station.

39. The wireless network of claim 37, wherein the at least one usability factor includes a cost associated with the respective base station receiving control of the mobile unit.

40. The wireless network of claim 37, wherein the at least one usability factor includes a load of the respective base station and a cost associated with the respective base station receiving control of the mobile unit.