Dynamically configured wireless communications, for example, in automatic data collection environment

• US 8,014,354 B2
• Filed: 10/17/2008
• Issued: 09/06/2011
• Est. Priority Date: 10/17/2008
• Status: Active Grant

• Current Assignee: Intermec IP Corporation (Honeywell International Inc.)
• Original Assignee: Intermec IP Corporation (Honeywell International Inc.)
• Inventors: Eichenberger, John, Albro, Marcus
• Primary Examiner(s): Phunkulh; Bob A
• Application Number:
  US12/253,678
• Publication Number:
  US 20100097982A1
• Time in Patent Office: 1,054 Days
• Field of Search: None
• US Class Current: 370/330
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

Dynamic configuration of a wireless environment, for example a wireless automatic data collection environment adjust various thresholds that trigger searching or scanning for new wireless access points (WAPs) and/or roaming. Thresholds may be increased or decreased based on various outcomes.

Claims

1. A method of providing dynamically updated wireless communications, the method comprising:

determining if a signal strength of a current wireless access point with which wireless communications is established is below an adjustable search triggering signal strength threshold;

searching for any additional wireless access points if the signal strength of the current wireless access point is determined to be below the adjustable search triggering signal strength threshold;

determining if a signal strength of at least one new wireless access point located by the searching is at least equal to a roam triggering signal strength threshold;

roaming if the signal strength of the at least one new wireless access point located by the searching is at least equal to the roam triggering signal strength threshold; and

adjusting the adjustable search triggering signal strength threshold if no new wireless access point has a signal strength that is at least equal to the roam triggering signal strength threshold.

2. The method of claim 1 wherein adjusting the adjustable scanning signal strength threshold if no new wireless access point has a signal strength that is at least equal to the roam triggering signal strength threshold includes decreasing the adjustable search triggering signal strength threshold.

3. The method of claim 1, further comprising:

setting the roam triggering signal strength threshold based on the signal strength of the current wireless access point.

4. The method of claim 3 wherein setting the roam triggering signal strength threshold based on the signal strength of the current wireless access point includes setting the roam triggering signal strength threshold at a defined roaming margin above the signal strength of the current wireless access point.

5. The method of claim 1, further comprising:

determining whether adjusting the adjustable search triggering signal strength threshold will make the adjustable search triggering signal strength threshold less than a defined minimum adjustable search triggering signal strength threshold value, wherein adjusting the adjustable search triggering signal strength threshold if no new wireless access point has a signal strength that is at least equal to the roam triggering signal strength threshold includes decreasing the adjustable search triggering signal strength threshold only if the decreasing will not make the adjustable search triggering signal strength threshold less than the defined minimum adjustable search triggering signal strength threshold value.

6. The method of claim 1 wherein adjusting the adjustable scanning signal strength threshold if no new wireless access point has a signal strength that is at least equal to the roam triggering signal strength threshold includes adjusting the adjustable search triggering signal strength threshold if no new wireless access point has a signal strength that is at least equal to the roam triggering signal strength threshold over a first duration.

7. The method of claim 1, further comprising:

determining if a signal strength of the current wireless access point is at least equal to an adjustment triggering signal strength threshold; and

adjusting the adjustable search triggering signal strength threshold if the signal strength of the current wireless access point is at least equal to the adjustment triggering signal strength threshold.

8. The method of claim 7 wherein adjusting the adjustable search triggering signal strength threshold if the signal strength of the current wireless access point is at least equal to the adjustment triggering signal strength threshold includes increasing the adjustable search trigger signal strength threshold if the signal strength of the current wireless access point is at least equal to the adjustment triggering signal strength threshold.

9. The method of claim 7, further comprising:

setting the adjustment triggering signal strength threshold based on a current value of the adjustable search triggering strength threshold.

10. The method of claim 7 wherein adjusting the adjustable search triggering signal strength threshold if the signal strength of the current wireless access point is at least equal to the adjustment triggering signal strength threshold includes adjusting the adjustable search trigger signal strength threshold if the signal strength of the current wireless access point is at least equal to the adjustment triggering signal strength threshold over a second duration.

11. The method of claim 1, further comprising:

wirelessly communicating with a first wireless access point as the current wireless access point before roaming; and

wirelessly communicating with a second wireless access point as the current wireless access point after roaming.

12. The method of claim 1 wherein searching for any additional wireless access points if the signal strength of the current wireless access point is determined to be below the adjustable search triggering signal strength threshold includes scanning for additional wireless access points.

13. The method of claim 12 wherein scanning for additional wireless access points includes scanning a first subset of available channels at a first rate.

14. The method of claim 13 wherein scanning for additional wireless access points includes scanning a second subset of available channels at a second rate, lower than the first rate.

15. The method of claim 14, further comprising:

performing a divide and truncate operation on the total number of available channels to define the size of at least the first and the second subsets.

16. The method of claim 14, further comprising:

performing a divide by 3 and truncate operation on the total number of available channels to define the size of at least the first and the second subsets.

17. The method of claim 13, further comprising:

including the one of the available channels that is currently used for wireless communications in the first subset.

18. The method of claim 17, further comprising:

including a number of the available channels identified in an access point neighbor report in the first subset.

19. A wireless communications system, the system comprising:

at least one antenna;

at least one transmitter communicatively coupled to the at least one antenna;

at least one receiver communicatively coupled to the at least one antenna;

at least one control system communicatively coupled to the at least one transmitter and the at least one receive, the control system that dynamically updates wireless communications by;

determining if a signal strength of a current wireless access point with which wireless communications is established is below an adjustable search triggering signal strength threshold;

searching for any additional wireless access points if the signal strength of the current wireless access point is determined to be below the adjustable search triggering signal strength threshold;

determining if a signal strength of at least one new wireless access point located by the searching is at least equal to a roam triggering signal strength threshold;

roaming if the signal strength of the at least one new wireless access point located by the searching is at least equal to the roam triggering signal strength threshold; and

decreasing the adjustable search triggering signal strength threshold if no new wireless access point has a signal strength that is at least equal to the roam triggering signal strength threshold.

20. The wireless communications system of claim 19 wherein the control system dynamically updates wireless communications further by:

setting the roam triggering signal strength threshold at a defined first margin above a current value of the adjustable search triggering strength threshold.

21. The wireless communications system of claim 19, further comprising:

setting the adjustable search triggering signal strength threshold to the defined minimum adjustable search triggering signal strength threshold value if adjustment of the adjustable search triggering signal strength threshold brings the adjustable search triggering signal strength threshold below the defined minimum adjustable search triggering signal strength threshold value.

22. The wireless communications system of claim 19 wherein the control system dynamically updates wireless communications further by:

determining if a signal strength of the current wireless access point is at least equal to the an adjustment triggering signal strength threshold; and

increasing the adjustable search triggering signal strength threshold if the signal strength of the current wireless access point is at least equal to the adjustment triggering signal strength threshold.

23. The wireless communications system of claim 19 wherein the control system dynamically updates wireless communications further by:

setting the roam triggering signal strength threshold at a defined second margin above the current value of the adjustable search triggering strength threshold.

24. The wireless communications system of claim 19 wherein the control system dynamically updates wireless communications further by:

performing a divide and truncate operation on the total number of available channels to define the size of at least the first and the second subsets.

25. The wireless communications system of claim 19 wherein the control system dynamically updates wireless communications further by:

including the one of the available channels that is currently used for wireless communications in the first subset; and

including a number of the available channels identified in an access point neighbor report in the first subset.

26. The wireless communications system of claim 19 wherein the control system includes at least one processor and at least one processor-readable storage medium that stores processor executable instructions to configure the processor.