Secure ranging with passive devices

A second user equipment (UE) for wireless communication, comprising:

• memory;
• and
• one or more processors coupled to the memory, the memory comprising instructions executable by the one or more processors to cause the second UE to:
• transmit, to a first UE via reflection by one or more passive devices, a first reference signal (RS) that is based at least in part on a first key that is shared with the first UE and that corresponds to a configuration of the one or more passive devices, wherein the configuration includes a timing of when each of the one or more passive devices is active or inactive;
• receive, from the first UE via reflection by the one or more passive devices and in association with the transmitting of the first RS, a second RS that is based at least in part on the first key;
• generate a second key based at least in part on a measurement of the second RS on a channel that is established between the first UE and the second UE according to the configuration of the one or more passive devices;
• receive a positioning reference signal (PRS) that includes an indication of being generated with the second key;
• and
• verify, based on the second key, whether generation of the PRS is secure.

A method of wireless communication performed by a first user equipment (UE), comprising:

• transmitting, to a second UE via reflection by one or more passive devices, a first reference signal (RS) that is based at least in part on a first key that is shared with the second UE and that corresponds to a configuration of the one or more passive devices, wherein the configuration includes a timing of when each of the one or more passive devices is active or inactive;
• receiving, from the second UE via reflection by the one or more passive devices and in association with the transmitting of the first RS, a second RS that is based at least in part on the first key;
• generating a second key based at least in part on a measurement of the second RS on a channel that is established between the first UE and the second UE according to the configuration of the one or more passive devices;
• and
• transmitting a positioning reference signal (PRS) that is based at least in part on the second key and that is associated with a measurement of a range between the first UE and the second UE.

A method of wireless communication performed by a second user equipment (UE), comprising:

• transmitting, to a first UE via reflection by one or more passive devices, a first reference signal (RS) that is based at least in part on a first key that is shared with the first UE and that corresponds to a configuration of the one or more passive devices, wherein the configuration includes a timing of when each of the one or more passive devices is active or inactive;
• receiving, from the first UE via reflection by the one or more passive devices and in association with the transmitting of the first RS, a second RS that is based at least in part on the first key;
• generating a second key based at least in part on a measurement of the second RS on a channel that is established between the first UE and the second UE according to the configuration of the one or more passive devices;
• receiving a positioning reference signal (PRS) that includes an indication of being generated with the second key;
• and
• verifying, based on the second key, whether generation of the PRS is secure.