IP Library Granted Patent US 12,418,845
Granted Patent B2
US 12,418,845 · App. 18/150,409 · Granted Sep 16, 2025

Wireless local area network (WLAN) roaming optimizations utilizing a reconfigurable intelligent surface (RIS) device

Inventors: Jerome Henry (Pittsboro, NC); Robert Edgar Barton (Richmond, CA); Indermeet Singh Gandhi (San Jose, CA)
Assignee: CISCO TECHNOLOGY, INC.
H04W36/00837H04W36/30H04W36/32
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Quick Facts
Patent No.
US 12,418,845
App. No.
18/150,409
Granted
Sep 16, 2025
Kind
B2
Abstract

Provided herein are techniques through which coordinated steering of a Reconfigurable Intelligent Surface (RIS) device can be utilized according to prioritized time-slices determined for each of multiple wireless access points (APs) for a wireless local area network (WLAN). Coordinated steering of an RIS device by multiple wireless APs according to prioritized time-slices may facilitate seamless roaming for wireless clients between the wireless APs for the WLAN.

Claims (34)

1. A method, comprising:

determining prioritized time-slices for utilizing a Reconfigurable Intelligent Surface (RIS) device by at least a first wireless access point (AP) and a second wireless AP for a wireless local area network, wherein the first wireless AP is provided a first prioritized time-slice in which to utilize the RIS device and the second wireless AP is provided a second prioritized time-slice in which to utilize the RIS device;

determining that a wireless client having a first communication session involving the first wireless AP is to be transitioned to a second communication session involving the second wireless AP, wherein the first wireless AP utilizes a first configuration of a plurality of configurable reflecting elements of the RIS device for communications with the wireless client via the first communication session during the first prioritized time-slice for utilizing the RIS device;

identifying a second configuration of the plurality of configurable reflecting elements of the RIS device to facilitate the second communication session for the wireless client involving the second wireless AP; and

triggering the wireless client to roam from the first wireless AP to the second wireless AP for establishing the second communication session involving the second wireless AP, wherein the second wireless AP utilizes the second configuration of the plurality of configurable reflecting elements of the RIS device for communications with the wireless client via the second communication session during the second prioritized time-slice for utilizing the RIS device.

2. The method of claim 1 , wherein the second configuration of the plurality of configurable reflecting elements of the RIS device is determined during the second prioritized time-slice for utilizing the RIS device.

3. The method of claim 2 , wherein the second configuration of the plurality of configurable reflecting elements is determined through one or more probe exchanges between the second wireless AP and the wireless client.

4. The method of claim 1 , wherein the second configuration of the plurality of configurable reflecting elements of the RIS device is determined based on historical information indicating a particular configuration of the plurality of configurable reflecting elements of the RIS device based on at least one of a location of the wireless client or signal strength information for the first communication session involving the first wireless AP.

5. The method of claim 1 , wherein the first wireless AP notifies the second wireless AP that the first communication session of the wireless client involving the first wireless AP involves the first wireless AP utilizing the RIS device.

6. The method of claim 1 , wherein the first prioritized time-slice provides a larger period of time for utilizing the RIS device by the first wireless AP than the second prioritized time-slice.

7. The method of claim 1 , wherein the triggering is initiated based on determining that signal strength or channel quality between the wireless client and the second wireless AP would be improved in comparison to signal strength or channel quality between the wireless client and the first wireless AP.

8. The method of claim 1 , wherein the method is performed based on communications between the first wireless AP and the second wireless AP.

9. The method of claim 1 , wherein the communications between the first wireless AP and the second wireless AP are facilitated by a controller device that controls both the first wireless AP and the second wireless AP.

10. One or more non-transitory computer readable storage media encoded with instructions that, when executed by a processor, cause the processor to perform operations, comprising:

determining prioritized time-slices for utilizing a Reconfigurable Intelligent Surface (RIS) device by at least a first wireless access point (AP) and a second wireless AP for a wireless local area network, wherein the first wireless AP is provided a first prioritized time-slice in which to utilize the RIS device and the second wireless AP is provided a second prioritized time-slice in which to utilize the RIS device;

determining that a wireless client having a first communication session involving the first wireless AP is to be transitioned to a second communication session involving the second wireless AP, wherein the first wireless AP utilizes a first configuration of a plurality of configurable reflecting elements of the RIS device for communications with the wireless client via the first communication session during the first prioritized time-slice for utilizing the RIS device;

identifying a second configuration of the plurality of configurable reflecting elements of the RIS device to facilitate the second communication session for the wireless client involving the second wireless AP; and

triggering the wireless client to roam from the first wireless AP to the second wireless AP for establishing the second communication session involving the second wireless AP, wherein the second wireless AP utilizes the second configuration of the plurality of configurable reflecting elements of the RIS device for communications with the wireless client via the second communication session during the second prioritized time-slice for utilizing the RIS device.

11. The media of claim 10 , wherein the second configuration of the plurality of configurable reflecting elements of the RIS device is determined during the second prioritized time-slice for utilizing the RIS device.

12. The media of claim 11 , wherein the second configuration of the plurality of configurable reflecting elements is determined through one or more probe exchanges between the second wireless AP and the wireless client.

13. The media of claim 10 , wherein the second configuration of the plurality of configurable reflecting elements of the RIS device is determined based on historical information indicating a particular configuration of the plurality of configurable reflecting elements of the RIS device based on at least one of a location of the wireless client or signal strength information for the first communication session involving the first wireless AP.

14. The media of claim 10 , wherein the first wireless AP notifies the second wireless AP that the first communication session of the wireless client involving the first wireless AP involves the first wireless AP utilizing the RIS device.

15. A system comprising:

at least one memory element for storing data; and

at least one processor for executing instructions associated with the data, wherein executing the instructions causes the system to perform operations, comprising:

determining prioritized time-slices for utilizing a Reconfigurable Intelligent Surface (RIS) device by at least a first wireless access point (AP) and a second wireless AP for a wireless local area network, wherein the first wireless AP is provided a first prioritized time-slice in which to utilize the RIS device and the second wireless AP is provided a second prioritized time-slice in which to utilize the RIS device;

determining that a wireless client having a first communication session involving the first wireless AP is to be transitioned to a second communication session involving the second wireless AP, wherein the first wireless AP utilizes a first configuration of a plurality of configurable reflecting elements of the RIS device for communications with the wireless client via the first communication session during the first prioritized time-slice for utilizing the RIS device;

identifying a second configuration of the plurality of configurable reflecting elements of the RIS device to facilitate the second communication session for the wireless client involving the second wireless AP; and

triggering the wireless client to roam from the first wireless AP to the second wireless AP for establishing the second communication session involving the second wireless AP, wherein the second wireless AP utilizes the second configuration of the plurality of configurable reflecting elements of the RIS device for communications with the wireless client via the second communication session during the second prioritized time-slice for utilizing the RIS device.

16. The system of claim 15 , wherein the second configuration of the plurality of configurable reflecting elements of the RIS device is determined during the second prioritized time-slice for utilizing the RIS device.

17. The system of claim 16 , wherein the second configuration of the plurality of configurable reflecting elements is determined through one or more probe exchanges between the second wireless AP and the wireless client.

18. The system of claim 15 , wherein the second configuration of the plurality of configurable reflecting elements of the RIS device is determined based on historical information indicating a particular configuration of the plurality of configurable reflecting elements of the RIS device based on at least one of a location of the wireless client or signal strength information for the first communication session involving the first wireless AP.

19. The system of claim 15 , wherein the first wireless AP notifies the second wireless AP that the first communication session of the wireless client involving the first wireless AP involves the first wireless AP utilizing the RIS device.

20. The system of claim 15 , wherein the triggering is initiated based on determining that signal strength or channel quality between the wireless client and the second wireless AP would be improved in comparison to signal strength or channel quality between the wireless client and the first wireless AP.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 5, 2023
From: HENRY, JEROME; BARTON, ROBERT EDGAR; GANDHI, INDERMEET SINGH
To: CISCO TECHNOLOGY, INC.
Reel/Frame 062285/0099 →
Continuity (1)
Related Publication 20240236784A1 · Jul 11, 2024
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