Time offsets in ultra-wideband (UWB) ranging
In some implementations, a first ultra-wideband (UWB) device may determine a respective time offset for each scrambled timestamp sequence (STS) in a series of STS used for ranging in a UWB ranging session between the first UWB device and the second UWB device, wherein the respective time offset for each STS in the series of STS is determined in accordance with time offset information shared between the first UWB device and the second UWB device. The first UWB device may transmit the series of STS via UWB radio frequency (RF) signals during the UWB ranging session, wherein each STS in the series of STS is transmitted with the respective time offset.
1. A method of enabling secure ultra-wideband (UWB) ranging between a first UWB device and a second UWB device, the method comprising:
determining, at the first UWB device, a respective time offset for each scrambled timestamp sequence (STS) in a series of STS used for ranging in a UWB ranging session between the first UWB device and the second UWB device, wherein the respective time offset for each STS in the series of STS:
varies from one STS to another in the series of STS,
is determined in accordance with time offset information shared between the first UWB device and the second UWB device using an in-band or out-of-band (OOB) link, and
comprises a change to a transmission time of the each STS in the series of STS from an expected transmission time; and
transmitting, with the first UWB device, the series of STS via UWB radio frequency (RF) signals during the UWB ranging session, wherein each STS in the series of STS is transmitted with the respective time offset.
2. The method of claim 1 , wherein each STS in the series of STS comprises a respective series of pulses, and wherein the respective time offset for each STS in the series of STS comprises a respective time offset for each pulse in the respective series of pulses.
3. The method of claim 2 , wherein the respective time offset for each pulse in the respective series of pulses is less than or equal to a duration of a pulse in the respective series of pulses.
4. The method of claim 2 , wherein the respective time offset for each pulse in the respective series of pulses varies from one pulse to another in the respective series of pulses.
5. The method of claim 1 , wherein the time offset information is shared between the first UWB device and the second UWB device prior to the UWB ranging session using non-UWB RF communication.
6. The method of claim 1 , wherein the time offset information is shared between the first UWB device and the second UWB device in a ranging control message (RCM) of the UWB ranging session.
7. The method of claim 1 , wherein the UWB ranging session comprises a narrowband (NB) UWB ranging session.
8. A method of enabling secure ultra-wideband (UWB) ranging between a first UWB device and a second UWB device, the method comprising:
determining, at the second UWB device, a respective time offset for each scrambled timestamp sequence (STS) in a series of STS used for ranging in a UWB ranging session between the first UWB device and the second UWB device, wherein the respective time offset for each STS in the series of STS:
varies from one STS to another in the series of STS,
is determined in accordance with time offset information shared between the first UWB device and the second UWB device using an in-band or out-of-band (OOB) link, and
comprises a change to a transmission time of the each STS in the series of STS from an expected transmission time; and
receiving, with the second UWB device, the series of STS via UWB radio frequency (RF) signals during the UWB ranging session, wherein each STS in the series of STS is received with the respective time offset.
9. The method of claim 8 , wherein each STS in the series of STS comprises a respective series of pulses, and wherein the respective time offset for each STS in the series of STS comprises a respective time offset for each pulse in the respective series of pulses.
10. The method of claim 9 , wherein the respective time offset for each pulse in the respective series of pulses is less than or equal to a duration of a pulse in the respective series of pulses.
11. The method of claim 9 , wherein the respective time offset for each pulse in the respective series of pulses varies from one pulse to another in the respective series of pulses.
12. The method of claim 8 , wherein the time offset information is shared between the first UWB device and the second UWB device prior to the UWB ranging session using non-UWB RF communication.
13. The method of claim 8 , wherein the time offset information is shared between the first UWB device and the second UWB device in a ranging control message (RCM) of the UWB ranging session.
14. The method of claim 8 , wherein the UWB ranging session comprises a narrowband (NB) UWB ranging session.
15. A first ultra-wideband (UWB) device, comprising:
a transceiver;
a memory; and
one or more processors communicatively coupled with the transceiver and the memory, wherein the one or more processors are configured to:
determine a respective time offset for each scrambled timestamp sequence (STS) in a series of STS used for ranging in a UWB ranging session between the first UWB device and a second UWB device, wherein the respective time offset for each STS in the series of STS:
varies from one STS to another in the series of STS,
is determined in accordance with time offset information shared between the first UWB device and the second UWB device using an in-band or out-of-band (OOB) link, and
comprises a change to a transmission time of the each STS in the series of STS from an expected transmission time; and
transmit, via the transceiver, the series of STS via UWB radio frequency (RF) signals during the UWB ranging session, wherein each STS in the series of STS is transmitted with the respective time offset.
16. The first UWB device of claim 15 , wherein the one or more processors are configured to determine the respective time offset such that each STS in the series of STS comprises a respective series of pulses, and wherein the respective time offset for each STS in the series of STS comprises a respective time offset for each pulse in the respective series of pulses.
17. The first UWB device of claim 16 , wherein the one or more processors are configured to determine the respective time offset such that the respective time offset for each pulse in the respective series of pulses is less than or equal to a duration of a pulse in the respective series of pulses.
18. The first UWB device of claim 15 , wherein the one or more processors are further configured to share the time offset information between the first UWB device and the second UWB device prior to the UWB ranging session using non-UWB RF communication.
19. The first UWB device of claim 15 , wherein the one or more processors are further configured to share the time offset information between the first UWB device and the second UWB device in a ranging control message (RCM) of the UWB ranging session.
20. The first UWB device of claim 15 , wherein the UWB ranging session comprises a narrowband (NB) UWB ranging session.
21. A second ultra-wideband (UWB) device, comprising:
a transceiver;
a memory; and
one or more processors communicatively coupled with the transceiver and the memory, wherein the one or more processors are configured to:
determine a respective time offset for each scrambled timestamp sequence (STS) in a series of STS used for ranging in a UWB ranging session between a first UWB device and the second UWB device, wherein the respective time offset for each STS in the series of STS:
varies from one STS to another in the series of STS,
is determined in accordance with time offset information shared between the first UWB device and the second UWB device using an in-band or out-of-band (OOB) link, and
comprises a change to a transmission time of the each STS in the series of STS from an expected transmission time; and
receive, via the transceiver, the series of STS via UWB radio frequency (RF) signals during the UWB ranging session, wherein each STS in the series of STS is received with the respective time offset.
22. The second UWB device of claim 21 , wherein the one or more processors are configured to determine the respective time offset such that each STS in the series of STS comprises a respective series of pulses, and wherein the respective time offset for each STS in the series of STS comprises a respective time offset for each pulse in the respective series of pulses.
23. The second UWB device of claim 21 , wherein the time offset information is shared between the first UWB device and the second UWB device: (i) prior to the UWB ranging session using non-UWB RF communication, or (ii) in a ranging control message (RCM) of the UWB ranging session.
24. The second UWB device of claim 21 , wherein the UWB ranging session comprises a narrowband (NB) UWB ranging session.