Angle of arrival location sensing with antenna array

Patent metadata

Field	Value
Publication number	US-11513181-B2
Application number	US-202016939614-A
Country	US
Kind code	B2
Filing date	Jul 27, 2020
Priority date	May 3, 2013
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

In one embodiment, a method includes receiving a plurality of radio frequency chains at a wireless device in a block based modulation environment, recording subcarrier phases and differences between the subcarrier phases, and using the subcarrier phase differences to construct a feature vector for use in angle of arrival calculated positioning of a mobile device.

First claim

What is claimed is:

1. A method comprising:
at a wireless device in a block based modulation environment, receiving a single packet with a plurality of radio frequency chains;
at the wireless device, recording subcarrier phases and differences between said subcarrier phases for the single packet received by different radio frequency chains; and
using said subcarrier phase differences to construct a feature vector for use in angle of arrival calculated positioning of a mobile device relative to the wireless device.

2. The method of claim 1 wherein the wireless device comprises an indoor mounted access point.

3. The method of claim 1 wherein the wireless device comprises another mobile device.

4. The method of claim 1 , further comprising receiving a sequence of null data packet announcement and null data packets with a common antenna, wherein the single packet is among the sequence received with the common antenna.

5. The method of claim 1 wherein the block based modulation environment comprises an Orthogonal Frequency Division Multiplexing system.

6. The method of claim 1 wherein the block based modulation environment comprises a Wi-Fi network.

7. An apparatus comprising:
a plurality of radio frequency chains for receiving a single packet in a block based modulation environment; and
a processor configured for performing operations including recording subcarrier phases and differences between said subcarrier phases for the single packet received by different radio frequency chains, and using said subcarrier phase differences to construct a feature vector for use in angle of arrival calculated positioning of a mobile device relative to the apparatus; and
memory for storing said subcarrier phases and said feature vector.

8. The apparatus of claim 7 wherein the apparatus comprises an indoor mounted access point.

9. The apparatus of claim 7 wherein the apparatus comprises another mobile device.

10. The apparatus of claim 7 wherein the processor is configured to process a sequence of null data packet announcement and null data packets with a common antenna, wherein the single packet is among the sequence received with the common antenna.

11. The apparatus of claim 7 wherein the block based modulation environment comprises an Orthogonal Frequency Division Multiplexing system.

12. The apparatus of claim 7 wherein the block based modulation environment comprises a Wi-Fi network.

13. Logic encoded on one or more non-transitory computer readable media for execution and when executed operable to:
process a single packet with a plurality of radio frequency chains at a wireless device in a block based modulation environment;
record subcarrier phases and differences between said subcarrier phases for the single packet processed by the different radio frequency chains; and
construct a feature vector using said subcarrier phase differences for use in angle of arrival calculated positioning of a mobile device relative to the wireless device.

14. The logic of claim 13 wherein the wireless device comprises an indoor mounted access point.

15. The logic of claim 13 wherein the wireless device comprises another mobile device.

16. The logic of claim 13 wherein the logic is further operable to process a sequence of null data packet announcement and null data packets received with a common antenna, wherein the single packet is among the sequence received with the common antenna.

17. The logic of claim 13 wherein the block based modulation environment comprises an Orthogonal Frequency Division Multiplexing system.

18. The logic of claim 13 wherein the block based modulation environment comprises a Wi-Fi network.

Assignees

• Cisco Tech Inc

Inventors

• Hart Brian Donald
• Stager Paul J
• Pandey Santosh
• Kloper David
• Lyons Dan
• Silverman Matthew A

Classifications

• G01S3/48 Primary

  the waves arriving at the antennas being continuous or intermittent and the phase difference of signals derived therefrom being measured · CPC title

• G01S1/68

  Marker, boundary, call-sign, or like beacons transmitting signals not carrying directional information · CPC title

• H04W64/006

  with additional information processing, e.g. for direction or speed determination · CPC title

• G01S3/38 Primary

  using adjustment of real or effective orientation of directivity characteristic of an antenna or an antenna system to give a desired condition of signal derived from that antenna or antenna system, e.g. to give a maximum or minimum signal (G01S3/16, G01S3/28 take precedence) · CPC title