Device to device round-trip time (RTT) measurement via neighbor aware network

摘要

Methods and systems for performing a round trip time determination between two devices are described. An example method may include publishing, over a wireless network interface by a first device within a neighbor aware network (NAN) cluster, a schedule that invites devices within the NAN cluster to request, within a time window, to perform a round trip time (RTT) determination with the first device. The schedule may indicate that the time window begins at a time offset from a NAN discovery window and ends after a predetermined period of time has elapsed. The method may also include receiving a request, from a second device within the NAN cluster, to perform the RTT determination with the first device. The method may also include performing the RTT determination with the second device.

主权项

1. A method comprising: publishing, over a wireless network interface by a first device within a neighbor aware network (NAN) cluster, a schedule that invites devices within the NAN cluster to request, within a time window, to perform a round trip time (RTT) determination with the first device, wherein the schedule indicates that the time window begins at a time offset from a NAN discovery window and ends after a predetermined period of time has elapsed, wherein the NAN cluster is operating on a wireless local area network (WLAN) channel;
the first device operating, during the time window, in a WLAN infrastructure mode in which the first device is connected to a wireless access point; receiving a NAN synchronization frame during the NAN discovery window that indicates a timer value, the timer value enabling the devices within the NAN cluster to synchronize respective clocks; receiving a request, within the time window from a second device within the NAN cluster, to perform the RTT determination with the first device; based on receiving the request within the time window, performing fully within the time window the RTT determination with the second device that is also within the NAN cluster, wherein performing the RTT determination comprises:
sending an echo request message to the second device;generating, based on a timer that is synchronized to the NAN cluster and adjusted based on the time value, a first time stamp that indicates a time at which the echo request message was sent;receiving an echo message;in response to receiving the echo message, generating, based on the timer, a second time stamp that indicates a time at which the echo message was received; anddetermining the RTT based on the first time stamp and the second time stamp; determining, based on the timer that is synchronized to the NAN cluster, that the time offset from the NAN discovery window has elapsed; and responsive to the determination, transitioning from the WLAN infrastructure mode in which the first device is connected to the wireless access point to a NAN mode in which the first device is disconnected from the wireless access point and in which the device is configured to receive on the WLAN channel.