Location accuracy via intelligent reflecting surfaces

Patent metadata

Field	Value
Publication number	US-12471052-B2
Application number	US-202217989313-A
Country	US
Kind code	B2
Filing date	Nov 17, 2022
Priority date	Nov 17, 2022
Publication date	Nov 11, 2025
Grant date	Nov 11, 2025

Abstract

In some aspects, the techniques described herein relate to a method including: determining a series of predetermined phases for wireless signals to be used in location calculations for a station device accessing a wireless access point; reflecting wireless signals from the wireless access point off of an intelligent reflecting surface to the station device; and controlling the intelligent reflecting surface such that a series of the wireless signals are reflected off of the intelligent reflecting surface with the predetermined phases.

First claim

What is claimed is:

1 . A method comprising:
determining a series of predetermined phases for wireless signals to be used in location calculations to be performed by a station device accessing a wireless access point, wherein the determining comprises determining a series of orthogonal phase vectors; reflecting wireless signals from the wireless access point off of an intelligent reflecting surface to the station device; and controlling the intelligent reflecting surface such that a series of the wireless signals are reflected off of the intelligent reflecting surface with the predetermined phases for the location calculations to be performed by the station device, wherein each orthogonal phase vector of the series of orthogonal phase vectors corresponds to one state at which the intelligent reflecting surface is controlled.

2 . The method of claim 1 , wherein determining the series of orthogonal phase vectors comprises determining the series of orthogonal phase vectors using a Gram-Schmidt Orthonormalization algorithm.

3 . The method of claim 1 , wherein the intelligent reflecting surface is controlled to cause the wireless signals reflected off of the intelligent reflecting surface to transition from one phase of the predetermined phases to a next phase of the predetermined phases in response to detecting a specific message transmitted between the wireless access point and the station device.

4 . The method of claim 3 , wherein the specific message comprises a block-acknowledgment request message.

5 . The method of claim 1 , wherein controlling the intelligent reflecting surface comprises controlling the intelligent reflecting surface in response to the wireless access point entering an off-channel scanning operation.

6 . The method of claim 1 , wherein controlling the intelligent reflecting surface comprises controlling the intelligent reflecting surface based on channel state information for communications between the wireless access point and the station device.

7 . The method of claim 6 , wherein controlling the intelligent reflecting surface based on the channel state information comprises controlling the intelligent reflecting surface to eliminate reflected paths from the wireless signals obtained by the station device.

8 . The method of claim 7 , wherein controlling the intelligent reflecting surface based on the channel state information comprises controlling the intelligent reflecting surface to eliminate reflected paths from the wireless signals obtained by the station device includes controlling the intelligent reflecting surface to direct wireless signals incident on the intelligent reflecting surface away from the station device.

9 . The method of claim 1 , wherein controlling the intelligent reflecting surface comprises controlling the intelligent reflecting surface such that the intelligent reflecting surface provides the series of the wireless signals with the predetermined phases at a predetermined interval.

10 . The method of claim 9 , wherein the predetermined interval is based upon a beacon interval of the wireless access point.

11 . A method comprising:
obtaining, at a station device, a first wireless signal provided from a wireless access point along a path that includes an intelligent reflecting surface; obtaining, at the station device, a second wireless signal provided from the wireless access point along the path that includes the intelligent reflecting surface, wherein the second wireless signal is phase shifted relative to the first wireless signal by the intelligent reflecting surface according to a series of predetermined orthogonal phase vectors, wherein each predetermined orthogonal phase vector of the series of predetermined orthogonal phase vectors corresponds to one state at which the intelligent reflecting surface is controlled; and determining, by the station device, a location of the station device relative to the wireless access point based upon the first wireless signal and the second wireless signal.

12 . The method of claim 11 , wherein the first wireless signal is obtained during a first off-channel scanning operation of the wireless access point and the second wireless signal is obtained during a second off-channel scanning operation of the wireless access point.

13 . The method of claim 11 , wherein obtaining the second wireless signal comprises obtaining the second wireless signal in response to a block-acknowledgment request message provided from the station device to the wireless access point.

14 . The method of claim 13 , wherein the second wireless signal comprises a block acknowledgment message provided by the wireless access point in response to the block-acknowledgment request message.

15 . An apparatus comprising:
at least one intelligent reflecting surface; and one or more processors, wherein the one or more processors are configured to:
determine a series of predetermined phases for wireless signals to be used in location calculations to be performed by a station device accessing a wireless access point, wherein the determining comprises determining a series of orthogonal phase vectors; and
control the at least one intelligent reflecting surface such that a series of wireless signals, incident from a wireless access point, are reflected off of the at least one intelligent reflecting surface to the station device with the predetermined phases for the location calculations to be performed by the station device, wherein each orthogonal phase vector of the series of orthogonal phase vectors corresponds to one state at which the at least one intelligent reflecting surface is controlled.

16 . The apparatus of claim 15 , wherein the one or more processors are configured to determine the series of orthogonal phase vectors by determining the series of orthogonal phase vectors using a Gram-Schmidt Orthonormalization algorithm.

17 . The apparatus of claim 15 , further comprising one or more network interfaces, wherein the one or more processors are configured to control the at least one intelligent reflecting surface to cause the wireless signals reflected off of the at least one intelligent reflecting surface to transition from one phase of the predetermined phases to a next phase of the predetermined phases in response to detecting a block-acknowledgment request message via the one or more network interfaces.

18 . The apparatus of claim 15 , wherein the one or more processors are configured to control the at least one intelligent reflecting surface in response to the wireless access point entering an off-channel scanning operation.

19 . The apparatus of claim 15 , wherein the one or more processors are configured to control the at least one intelligent reflecting surface by controlling the at least one intelligent reflecting surface based on channel state information for communications between the wireless access point and the station device.

20 . The apparatus of claim 19 , wherein to control the at least one intelligent reflecting surface based on the channel state information comprises controlling the at least one intelligent reflecting surface to eliminate reflected paths from the wireless signals obtained by the station device.

Assignees

• Cisco Tech Inc

Inventors

• Alizadeh Ardalan
• Kalavakuru Sivadeep R
• Silverman Matthew Aaron
• Swartz John Matthew

Classifications

• H04L1/1607

  Details of the supervisory signal · CPC title

• H04W64/00 Primary

  Locating users or terminals {or network equipment} for network management purposes, e.g. mobility management · CPC title