Time of flight (ToF) measurement

• US 9,810,780 B2
• Filed: 11/02/2016
• Issued: 11/07/2017
• Est. Priority Date: 01/23/2013
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Ben-Haim, Shani, Amizur, Yuval, Segev, Jonathan
• Primary Examiner(s): Wong, Warner
• Application Number:
  US15/341,326
• Publication Number:
  US 20170052251A1
• Time in Patent Office: 370 Days
• Field of Search: 370241, 3702411, 370252, 370255, 370277-278, 370282, 370350, 370464-465, 370503
• CPC Class Codes: G01S 13/767 Responders; Transponders teaching or practice apparatus for gun-aiming or gun-laying using reflecting targets or active targets F41G3/26
• CPC Class Codes: G01S 5/10 Position of receiver fixed by co-ordinating a plurality of position lines defined by path-difference measurements , e.g. omega or decca systemsG01S5/12 takes precedence ; beacons and receivers cooperating therewith G01S1/306, G01S1/308
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location
• CPC Class Codes: H04L 7/0033 Correction by delay
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Embodiments of a communication station and method for time-of-flight (ToF) location determination in a wireless network are generally described herein. In some embodiments, a responding communication station receives a ToF measurement request. The responding communication station transmits an acknowledgment of the ToF measurement request. The responding communication station also transmits a response to the ToF measurement request that includes an indication of a time period for an initiating communication station to poll the responding communication station for a ToF result.

Claims

1. An apparatus comprising circuitry configured to cause a responding station to:

receive an initial time of flight (ToF) measurement request from an initiating station, the initial ToF measurement request comprising a measurement request bit indicating a request to perform a ToF measurement;

transmit a first acknowledgment (ACK) to the initiating station;

transmit a first responder ToF frame after the first ACK, the first responder ToF frame comprising a status field to indicate if the request to perform the ToF measurement is accepted or not accepted, the first responder ToF frame comprising an indication of a time period during which a subsequent ToF measurement request is to be transmitted;

receive a second ACK from the initiating station;

receive the subsequent ToF measurement request from the initiating station, the subsequent ToF measurement request comprising an indication of a request for ToF measurements;

transmit a third ACK to the initiating station; and

transmit to the initiating station another responder ToF frame comprising ToF measurements in a time of arrival (ToA) field and time of departure (ToD) field.

2. The apparatus of claim 1, wherein the first responder ToF frame comprises a zero value in a measurement field.

3. The apparatus of claim 1, wherein the ToA field comprises a measurement of a ToA of a transmission from the initiating station.

4. The apparatus of claim 1, wherein the ToD field comprises a measurement of a ToD of a transmission to the initiating station.

5. The apparatus of claim 1 comprising an access point (AP).

6. The apparatus of claim 1 comprising Physical Layer (PHY) circuitry, and processor circuitry.

7. The apparatus of claim 1 comprising an antenna, a memory, and a processor.

8. A product comprising a tangible computer-readable non-transitory storage medium comprising computer-executable instructions operable to, when executed by at least one processor, cause a responding station to:

receive an initial time of flight (ToF) measurement request from an initiating station, the initial ToF measurement request comprising a measurement request bit indicating a request to perform a ToF measurement;

transmit a first acknowledgment (ACK) to the initiating station;

transmit a first responder ToF frame after the first ACK, the first responder ToF frame comprising a status field to indicate if the request to perform the ToF measurement is accepted or not accepted, the first responder ToF frame comprising an indication of a time period during which a subsequent ToF measurement request is to be transmitted;

receive a second ACK from the initiating station;

receive the subsequent ToF measurement request from the initiating station, the subsequent ToF measurement request comprising an indication of a request for ToF measurements;

transmit a third ACK to the initiating station; and

transmit to the initiating station another responder ToF frame comprising ToF measurements in a time of arrival (ToA) field and time of departure (ToD) field.

9. The product of claim 8, wherein the responding station comprises an access point (AP).

10. The product of claim 8, wherein the first responder ToF frame comprises a zero value in a measurement field.

11. The product of claim 8, wherein the ToA field comprises a measurement of a ToA of a transmission from the initiating station.

12. The product of claim 8, wherein the ToD field comprises a measurement of a ToD of a transmission to the initiating station.

13. An apparatus comprising circuitry configured to cause an initiating station to:

transmit an initial time of flight (ToF) measurement request to a responding station, the initial ToF measurement request comprising a measurement request bit indicating a request to perform a ToF measurement;

receive a first acknowledgment (ACK) from the responding station;

receive a first responder ToF frame after the first ACK, the first responder ToF frame comprising a status field to indicate if the request to perform the ToF measurement is accepted or not accepted, the first responder ToF frame comprising an indication of a time period during which a subsequent ToF measurement request is to be transmitted;

transmit a second ACK to the responding station;

transmit the subsequent ToF measurement request to the responding station, the subsequent ToF measurement request comprising an indication of a request for ToF measurements;

receive a third ACK from the responding station; and

receive from the responding station another responder ToF frame comprising ToF measurements in a time of arrival (ToA) field and time of departure (ToD) field.

14. The apparatus of claim 13, wherein the first responder ToF frame comprises a zero value in a measurement field.

15. The apparatus of claim 13, wherein the circuitry is to trigger a round trip time calculation based on the ToF measurements in the ToA field and the ToD field.

16. The apparatus of claim 13, wherein the circuitry is to trigger a location calculation based on the ToF measurements in the ToA field and the ToD field.

17. The apparatus of claim 13 comprising a mobile wireless communicator.

18. The apparatus of claim 13 comprising Physical Layer (PHY) circuitry, and processor circuitry.

19. The apparatus of claim 13 comprising an antenna, a memory, and a processor.

20. A product comprising a tangible computer-readable non-transitory storage medium comprising computer-executable instructions operable to, when executed by at least one processor, cause an initiating station to:

transmit an initial time of flight (ToF) measurement request to a responding station, the initial ToF measurement request comprising a measurement request bit indicating a request to perform a ToF measurement;

receive a first acknowledgment (ACK) from the responding station;

receive a first responder ToF frame after the first ACK, the first responder ToF frame comprising a status field to indicate if the request to perform the ToF measurement is accepted or not accepted, the first responder ToF frame comprising an indication of a time period during which a subsequent ToF measurement request is to be transmitted;

transmit a second ACK to the responding station;

transmit the subsequent ToF measurement request to the responding station, the subsequent ToF measurement request comprising an indication of a request for ToF measurements;

receive a third ACK from the responding station; and

receive from the responding station another responder ToF frame comprising ToF measurements in a time of arrival (ToA) field and time of departure (ToD) field.

21. The product of claim 20, wherein the instructions, when executed, cause the initiating station to trigger a location calculation based on the ToF measurements in the ToA field and the ToD field.

22. The product of claim 20, wherein the first responder ToF frame comprises a zero value in a measurement field.

23. The product of claim 20, wherein the instructions, when executed, trigger a round trip time calculation based on the ToF measurements in the ToA field and the ToD field.