Passive location measurement

1. A device, the device comprising processing circuitry coupled to storage, the processing circuitry configured to:

initiate a passive trigger based (TB) ranging measurement with first device and a second device, wherein the passive TB ranging measurement comprises a passive TB ranging measurement phase followed by a passive TB ranging measurement reporting phase;

encode a downlink (DL) location measurement report (LMR) frame for transmission;

encode a trigger frame (TF) for transmission to the first device and second device; wherein the TF triggers the first device to send a first UL LMR the second device to send a second UL LMR;

encode, during the passive TB ranging measurement reporting phase, a first broadcast LMR comprising measurement information of the first device and the second device carried in the DL LMR; and

encode, during the passive TB ranging measurement reporting phase, a second broadcast LMR comprising the measurement information carried in first UL LMR and the second UL LMR.

2. The device of claim 1 , wherein at least part of the passive TB ranging measurement is decoded by a passive station device (PSTA).

3. The device of claim 1 , wherein the passive TB ranging measurement indicates to a passive station device (PSTA) to passively estimate its differential distance to other devices participating in the passive TB ranging measurement.

4. The device of claim 3 , wherein the PSTA is not an active transmitting participant in the passive TB ranging measurement.

5. The device of claim 1 , wherein the processing circuitry is further configured to encode the TF as a ranging TF of subtype passive TB measurement exchange.

6. The device of claim 1 , wherein the TF triggers the first device to send a first UL LMR the second device to send a second UL LMR.

7. The device of claim 1 , wherein the processing circuitry is further configured to decode a first UL NDP and a second UL NDP received from the first device and the second device respectively during the passive TB ranging measurement phase.

8. The device of claim 1 , wherein the first UL LMR comprises a sounding dialog token identifying a measurement phase in which timestamps were measured.

9. The device of claim 1 , further comprising a transceiver configured to transmit and receive wireless signals.

10. The device of claim 9 , further comprising an antenna coupled to the transceiver.

11. A non-transitory computer-readable medium storing computer-executable instructions which when executed by one or more processors result in performing operations comprising:

initiating a passive trigger based (TB) ranging measurement with first device and a second device, wherein the passive TB ranging measurement comprises a passive TB ranging measurement phase followed by a passive TB ranging measurement reporting phase;

encoding a downlink (DL) location measurement report (LMR) frame for transmission;

encoding a trigger frame (TF) for transmission to the first device and second device;

wherein the TF triggers the first device to send a first UL LMR the second device to send a second UL LMR;

encoding, during the passive TB ranging measurement reporting phase, a first broadcast LMR comprising measurement information of the first device and the second device carried in the DL LMR; and

encoding, during the passive TB ranging measurement reporting phase, a second broadcast LMR comprising the measurement information carried in first UL LMR and the second UL LMR.

12. The non-transitory computer-readable medium of claim 11 , wherein at least part of the passive TB ranging measurement is decoded by a passive station device (PSTA).

13. The non-transitory computer-readable medium of claim 11 , wherein the passive TB ranging measurement indicates to a passive station device (PSTA) to passively estimate its differential distance to other devices participating in the passive TB ranging measurement.

14. The non-transitory computer-readable medium of claim 13 , wherein the PSTA is not an active transmitting participant in the passive TB ranging measurement.

15. The non-transitory computer-readable medium of claim 11 , wherein the operations further comprise encoding the TF as a ranging TF of subtype passive TB measurement exchange.

16. The non-transitory computer-readable medium of claim 11 , wherein the TF triggers the first device to send a first UL LMR the second device to send a second UL LMR.

17. The non-transitory computer-readable medium of claim 11 , wherein the operations further comprise decoding a first UL NDP and a second UL NDP received from the first device and the second device respectively during the passive TB ranging measurement phase.

18. The non-transitory computer-readable medium of claim 11 , wherein the first UL LMR comprises a sounding dialog token identifying a measurement phase in which timestamps were measured.

19. A method comprising:

initiating, by one or more processors, a passive trigger based (TB) ranging measurement with first device and a second device, wherein the passive TB ranging measurement comprises a passive TB ranging measurement phase followed by a passive TB ranging measurement reporting phase;

encoding a downlink (DL) location measurement report (LMR) frame for transmission;

encoding a trigger frame (TF) for transmission to the first device and second device; wherein the TF triggers the first device to send a first UL LMR the second device to send a second UL LMR;

encoding, during the passive TB ranging measurement reporting phase, a first broadcast LMR comprising measurement information of the first device and the second device carried in the DL LMR; and

encoding, during the passive TB ranging measurement reporting phase, a second broadcast LMR comprising the measurement information carried in first UL LMR and the second UL LMR.

20. The method of claim 19 , wherein at least part of the passive TB ranging measurement is decoded by a passive station device (PSTA).