Centralized time synchronization for time difference of arrival (TDOA) using ultra-wideband (UWB)

A server 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:
• obtain metric information from each radio frequency (RF) positioning anchor of a group of RF positioning anchors, wherein the metric information of a respective RF positioning anchor comprises information indicating:
• a time source accessible to the respective RF positioning anchor,
• a ground truth accuracy of a known location of the respective RF positioning anchor,
• a clock stability of the respective RF positioning anchor,
• a geographic location of the respective RF positioning anchor,
• power consumption information of the respective RF positioning anchor, or
• a combination thereof,
• determine a weighted-closeness centrality value for each RF positioning anchor of the group of RF positioning anchors, wherein the weighted-closeness centrality value for each RF positioning anchor is based on:
• the metric information of the respective RF positioning anchor, and
• a value indicative of a number of hops of the respective RF positioning anchor to a plurality of other RF positioning anchors of the group of RF positioning anchors;
• select a synchronization reference anchor from the group of RF positioning anchors based at least in part on the weighted-closeness centrality value;
• and
• transmit, via the transceiver, information indicative of the selected synchronization reference anchor to each RF positioning anchor of the group of RF positioning anchors.

An apparatus for designating a synchronization reference anchor for a group of radio frequency (RF) positioning anchors to enable downlink Time Difference of Arrival (DL-TDoA) positioning of mobile devices, the apparatus comprising:

• means for obtaining metric information from each RF positioning anchor of the group of RF positioning anchors, wherein the metric information of a respective RF positioning anchor comprises information indicating:
• a time source accessible to the respective RF positioning anchor,
• a ground truth accuracy of a known location of the respective RF positioning anchor,
• a clock stability of the respective RF positioning anchor,
• a geographic location of the respective RF positioning anchor,
• power consumption information of the respective RF positioning anchor, or
• a combination thereof,
• means for determining a weighted-closeness centrality value for each RF positioning anchor of the group of RF positioning anchors, wherein the weighted-closeness centrality value for each RF positioning anchor is based on:
• the metric information of the respective RF positioning anchor, and
• a value indicative of a number of hops of the respective RF positioning anchor to a plurality of other RF positioning anchors of the group of RF positioning anchors;
• means for selecting the synchronization reference anchor from the group of RF positioning anchors based at least in part on the weighted-closeness centrality value;
• and
• means for transmitting information indicative of the selected synchronization reference anchor to each RF positioning anchor of the group of RF positioning anchors.

A non-transitory computer-readable medium storing instructions for designating a synchronization reference anchor for a group of radio frequency (RF) positioning anchors to enable downlink Time Difference of Arrival (DL-TDoA) positioning of mobile devices, the instructions comprising code for:

• obtaining metric information from each RF positioning anchor of the group of RF positioning anchors, wherein the metric information of a respective RF positioning anchor comprises information indicating:
• a time source accessible to the respective RF positioning anchor,
• a ground truth accuracy of a known location of the respective RF positioning anchor,
• a clock stability of the respective RF positioning anchor,
• a geographic location of the respective RF positioning anchor,
• power consumption information of the respective RF positioning anchor, or
• a combination thereof,
• determining a weighted-closeness centrality value for each RF positioning anchor of the group of RF positioning anchors, wherein the weighted-closeness centrality value for each RF positioning anchor is based on:
• the metric information of the respective RF positioning anchor, and
• a value indicative of a number of hops of the respective RF positioning anchor to a Plurality of other RF positioning anchors of the group of RF positioning anchors;
• selecting the synchronization reference anchor from the group of RF positioning anchors based at least in part on the weighted-closeness centrality value;
• and
• transmitting information indicative of the selected synchronization reference anchor to each RF positioning anchor of the group of RF positioning anchors.