Master-less device coordination in location positioning system

Patent metadata

Field	Value
Publication number	US-12405361-B2
Application number	US-202318400804-A
Country	US
Kind code	B2
Filing date	Dec 29, 2023
Priority date	Jun 3, 2020
Publication date	Sep 2, 2025
Grant date	Sep 2, 2025

Abstract

A communication device including a clock, a memory, and at least one processor is disclosed. The at least one processor is configured to execute instructions stored in the memory that cause the at least one processor to perform operations including receiving at least one message from a second communication device of a plurality of communication devices over a preconfigured time duration, determining a first local time of the clock of the communication device at which the at least one message from the second communication device is received, and determining a sync-time of the second communication device based on the at least one message from the second communication device. The operations include mapping the sync-time of the second communication device based on the first local time and the determined sync-time of the second communication device and adjusting a sync-time of the communication device based on the second local time.

First claim

What is claimed is:

1. A communication device of a plurality of communication devices, the communication device comprising:
a clock;
a first transceiver coupled with an antenna;
a second transceiver coupled with a transducer;
a memory; and
at least one processor configured to execute instructions stored in the memory that cause the at least one processor to perform operations comprising:
receiving at least one message from a second communication device of the plurality communication devices over a preconfigured time duration, the second communication device broadcasting a subsequent message to the at least one message at a time interval based on remaining battery power;
determining a first local time of the clock of the communication device at which the at least one message from the second communication device is received;
determining a sync-time of the second communication device based on the at least one message from the second communication device;
mapping the sync-time of the second communication device to a second local time of the clock of the communication device based on the first local time, and the determined sync-time of the second communication device;
adjusting a sync-time of the communication device based on the second local time; and
transmitting a first data or a second data as an acoustic signal for location positioning,
wherein the sync-time of the communication device corresponds with a first configurable offset from a reference time within which the first data is transmitted from the communication device to the plurality of communication devices, and
wherein the sync-time of the second communication device corresponds with a second configurable offset from the reference time within which the second data is transmitted from the second communication device to the plurality of communication devices.

2. The communication device of claim 1 , wherein the at least one message from the second communication device comprises first timing information that comprises at least one of a number of ticks since the sync-time of the second communication device, a timestamp of transmission of the at least one message from the second communication device, and an offset since the sync-time of the second communication device.

3. The communication device of claim 2 , wherein the at least one message from the second communication device further comprises an identifier of the second communication device.

4. The communication device of claim 1 , wherein the preconfigured time duration is not more than 60 seconds.

5. The communication device of claim 1 , wherein the operations further comprise:
receiving at least one message from a third communication device of the plurality of communication devices over the preconfigured time duration, wherein the at least one message from the third communication device comprises second timing information that indicates a sync-time of the third communication device, and an identifier of the third communication device;
determining a third local time of the clock of the communication device at which the at least one message from the third communication device is received;
determining the sync-time of the third communication device based on the second timing information;
mapping the sync-time of the third communication device to a fourth local time of the clock of the communication device based on the third local time, and the determined sync-time of the third communication device; and
adjusting the sync-time of the communication device based on an average of the second local time and the fourth local time.

6. The communication device of claim 1 , wherein the operations further comprise:
receiving at least one message from a third communication device of the plurality of communication devices over the preconfigured time duration, wherein the at least one message from the third communication device comprises second timing information that indicates a sync-time of the third communication device, and an identifier of the third communication device;
determining a third local time of the clock of the communication device at which the at least one message from the third communication device is received;
determining the sync-time of the third communication device based on the second timing information;
mapping the sync-time of the third communication device to a fourth local time of the clock of the communication device based on the third local time, and the determined sync-time of the third communication device; and
adjusting the sync-time of the communication device based on a smaller of the second local time and the fourth local time.

7. The communication device of claim 1 , wherein the clock has a frequency of 32768 hertz (Hz).

8. The communication device of claim 1 , wherein the operations further comprise receiving one or more identifiers of the plurality of communication devices to which the communication device is either authorized or not authorized to adjust the sync-time of the communication device.

9. The communication device of claim 1 , wherein the first data comprises location information of the communication device or the second data comprises location information of the second communication device, and wherein the communication device and the second communication device are base stations.

10. The communication device of claim 1 , wherein the first data or the second data is transmitted or received by the communication device or the second communication device as an acoustic signal for location positioning.

11. The communication device of claim 5 , wherein the operations further comprise:
transmitting at least one message from the communication device to the plurality of communication devices upon adjusting the sync-time of the communication device with respect to the second communication device and/or the third communication device, wherein the at least one message from the communication device comprises timing information that corresponds with the sync-time of the communication device, and an identifier of the communication device.

12. The communication device of claim 1 , wherein the first transceiver is a radio frequency transceiver, and the second transceiver is either an infrared transceiver or an acoustic transceiver, and wherein at least one message from the communication device is transmitted using the first transceiver or the second transceiver, or the at least one message from the second communication device is received using the first transceiver or the second transceiver.

13. The communication device of claim 1 , wherein the communication device or the second communication device is a portable tag or user equipment (UE) device.

14. The communication device of claim 1 , wherein the first data is transmitted using the first transceiver or the second transceiver.

15. A method, comprising:
receiving, at a first communication device of a plurality of communication devices, at least one message from a second communication device of the plurality of communication devices over a preconfigured time duration, the second communication device broadcasting a subsequent message to the at least one message at a time interval based on remaining battery power;
determining, at the first communication device, a first local time of a clock of the first communication device at which the at least one message from the second communication device is received;
determining, at the first communication device, a sync-time of the second communication device based on the at least one message from the second communication device;
mapping, at the first communication device, t

Assignees

• Sonitor Technologies As

Inventors

• Bakka Endre
• Booij Wilfred Edwin

Classifications

• H04W56/002

  Mutual synchronization · CPC title

• G01S11/08

  using synchronised clocks · CPC title

• G01S11/16 Primary

  using difference in transit time between electrical and acoustic signals · CPC title

• H04W56/0015 Primary

  one node acting as a reference for the others · CPC title