Techniques for improving ranging between electronic devices

Patent metadata

Field	Value
Publication number	US-2022299621-A1
Application number	US-202217805425-A
Country	US
Kind code	A1
Filing date	Jun 3, 2022
Priority date	Sep 25, 2020
Publication date	Sep 22, 2022
Grant date	—

Abstract

A mobile device may receive a plurality of timestamps, wherein the plurality of timestamps indicate sending and receiving time for ranging packets and response packets. The mobile device may calculate a responder turn-around time as a first difference between the second time and the first time. The mobile device may calculate a responding round trip time as a second difference between the second time and the third time. The mobile device may receive from the electronic device an initiator turn-around time and an initiator round trip time. The mobile device may calculate a frequency offset for the wireless protocol using the responder turn-around time, the responding round trip time, the initiator turn-around time, and the initiator round trip time. The mobile device may compare an observed frequency offset to the calculated frequency offset to determine a frequency offset difference and whether it exceeds a threshold, adjusting a ranging measurement.

First claim

What is claimed is:

1 . A method of ranging via a wireless protocol with an electronic device by a mobile device, the method performed by the mobile device comprising:
obtaining a first set of time measurements for signals sent and received by the mobile device for a ranging session between the mobile device and the electronic device; obtaining a second set of time measurements for signals sent and received by the electronic device for the ranging session; calculating a frequency offset between a first oscillator of the mobile device and a second oscillator of the electronic device using the first set of time measurements and the second set of time measurements; comparing an observed frequency offset to the calculated frequency offset to determine a frequency offset difference; and when the frequency offset difference exceeds a threshold, adjusting a ranging measurement.

2 . The method of claim 1 , wherein the observed frequency offset is determined from a measured signal of the wireless protocol of the electronic device.

3 . The method of claim 1 , further comprising calculating a range between the electronic device and the mobile device using the first set of time measurements and the second set of time measurements.

4 . The method of claim 1 , wherein obtaining the first set of time measurement includes:
receiving, via the wireless protocol, an information packet comprising a first timestamp from the electronic device in a first ranging packet, the first timestamp indicating a first transmission time of the first ranging packet; calculating a second timestamp indicating a second transmission time for the mobile device to transmit a response packet to the first ranging packet; wherein the method of claim 1 further comprises:
sending, via the wireless protocol, the calculated second timestamp to the electronic device.

5 . The method of claim 1 , wherein the adjusting the ranging measurement comprises applying a weighting to the ranging measurement based at least on the frequency offset difference.

6 . The method of claim 1 , further comprising displaying a previously calculated ranging based at least on the frequency offset difference.

7 . The method of claim 1 , further comprising calculating a direction to the electronic device based at least in part on received data packets.

8 . A mobile device configured to perform ranging via a wireless protocol with an electronic device, comprising:
a memory comprising computer-executable instructions; and one or more processors in communication with the memory and configured to access the memory and execute the computer-executable instructions to perform operations comprising:
obtaining a first set of time measurements for signals sent and received by the mobile device for a ranging session between the mobile device and the electronic device;
obtaining a second set of time measurements for signals sent and received by the electronic device for the ranging session;
calculating a frequency offset between a first oscillator of the mobile device and a second oscillator of the electronic device using the first set of time measurements and the second set of time measurements;
comparing an observed frequency offset to the calculated frequency offset to determine a frequency offset difference; and
when the frequency offset difference exceeds a threshold, adjusting a ranging measurement.

9 . The mobile device of claim 8 , wherein the observed frequency offset is determined from a measured signal of the wireless protocol of the electronic device.

10 . The mobile device of claim 8 , wherein the operations further comprise calculating a range between the electronic device and the mobile device using the first set of time measurements and the second set of time measurements.

11 . The mobile device of claim 8 , wherein obtaining the first set of time measurement includes:
receiving, via the wireless protocol, an information packet comprising a first timestamp from the electronic device in a first ranging packet, the first timestamp indicating a first transmission time of the first ranging packet; and calculating a second timestamp indicating a second transmission time for the mobile device to transmit a response packet to the first ranging packet; wherein the operations of claim 1 further comprise:
sending, via the wireless protocol, the calculated second timestamp to the electronic device.

12 . The mobile device of claim 8 , wherein the adjusting the ranging measurement comprises applying a weighting to the ranging measurement based at least on the frequency offset difference.

13 . The mobile device of claim 8 , wherein the operations further comprise displaying a previously calculated ranging based at least on the frequency offset difference.

14 . The mobile device of claim 8 , wherein the operations further comprise calculating a direction to the electronic device based at least in part on received data packets.

15 . One or more non-transitory computer-readable storage mediums comprising computer-executable instructions that, when executed by one or more processors, cause the one or more processors of a mobile device to perform operations to perform ranging via a wireless protocol with an electronic device, the operations comprising:
obtaining a first set of time measurements for signals sent and received by the mobile device for a ranging session between the mobile device and the electronic device; obtaining a second set of time measurements for signals sent and received by the electronic device for the ranging session; calculating a frequency offset between a first oscillator of the mobile device and a second oscillator of the electronic device using the first set of time measurements and the second set of time measurements; comparing an observed frequency offset to the calculated frequency offset to determine a frequency offset difference; and when the frequency offset difference exceeds a threshold, adjusting a ranging measurement.

16 . The one or more non-transitory computer-readable storage mediums of claim 15 , wherein the observed frequency offset is determined from a measured signal of the wireless protocol of the electronic device.

17 . The one or more non-transitory computer-readable storage mediums of claim 15 , wherein the operations further comprise calculating a range between the electronic device and the mobile device using the first set of time measurements and the second set of time measurements.

18 . The one or more non-transitory computer-readable storage mediums of claim 15 , wherein obtaining the first set of time measurements includes:
receiving, via the wireless protocol, an information packet comprising a first timestamp from the electronic device in a first ranging packet, the first timestamp indicating a first transmission time of the first ranging packet; and calculating a second timestamp indicating a second transmission time for the mobile device to transmit a response packet to the first ranging packet; wherein the operations of claim 1 further comprise:
sending, via the wireless protocol, the calculated second timestamp to the electronic device.

19 . The one or more non-transitory computer-readable storage mediums of claim 15 , wherein the adjusting the ranging measurement comprises applying a weighting to the ranging measurement based at least on the frequency offset difference.

20 . The one or more non-transitory computer-readable storage mediums of claim 15 , wherein the

Assignees

• Apple Inc

Inventors

• Werner Benjamin
• Mccracken Merrick
• Brumley Robert

Classifications

• G01S5/10

  Position of receiver fixed by co-ordinating a plurality of position lines defined by path-difference measurements {, e.g. omega or decca systems}(G01S5/12 takes precedence {; beacons and receivers cooperating therewith G01S1/306, G01S1/308}) · CPC title

• G01S5/0218

  Multipath in signal reception · CPC title

• G01S2013/468

  by Triangulation, i.e. two antennas or two sensors determine separately the bearing, direction or angle to a target, whereby with the knowledge of the baseline length, the position data of the target is determined · CPC title

• G01S5/0252

  Radio frequency fingerprinting · CPC title

• H04W64/006

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