Method and apparatus for obtaining location information using ranging block and ranging rounds

A non-transitory machine-readable medium comprising executable instructions that, when executed by a processing system including a processor operating from a mobile device, facilitate performance of operations, the operations comprising:

• overhearing REQ messages and RSP messages being wirelessly transmitted between each pair of a plurality of anchor pairs of a group of anchors according to a schedule that is generated by and provisioned by a server via a gateway to the group of anchors, wherein the plurality of anchor pairs operate as an initiator and a responder, respectively, in a location system, and wherein the schedule is for a ranging block, wherein the schedule directs only a subset of the group of anchors to engage in REQ and RSP messaging, wherein the ranging block is divided into a plurality of ranging rounds, wherein each ranging round of the plurality of ranging rounds is divided into two ranging slots, wherein each ranging round of the plurality of ranging rounds is dedicated to a respective anchor pair of the subset, and wherein during a first slot of the two ranging slots a respective REQ message is transmitted by a first anchor of the respective anchor pair of the subset and during a second slot of the two ranging slots a respective RSP message is transmitted by a second anchor of the respective anchor pair of the subset;
• calculating a TDOA measurement based on the REQ messages and RSP messages;
• and
• calculating location information based on the TDOA measurement, wherein the location information includes coordinates of the mobile device within a demarcated area, a speed of travel of the mobile device over a time period, a trajectory of the mobile device, and an angular orientation of the mobile device relative to a second subset of the group of anchors.

A method comprising:

• generating, by a server operating as a controller in a locating system, a schedule for a group of anchors operating as controlees in the location system that is utilized for determining position information for one or more mobile devices, wherein the schedule is for a ranging block, wherein the ranging block includes a plurality of ranging rounds, wherein each ranging round of the plurality of ranging rounds includes two ranging slots, and wherein the schedule directs only a subset of the group of anchors to engage in REQ and RSP messaging;
• determining a plurality of anchor pairs of the subset of the group of anchors comprising first anchors and second anchors based at least in part on anchor locations, wherein the anchor locations are known by the server and by the one or more mobile devices;
• and
• provisioning, by the server, the schedule to the group of anchors to cause the plurality of anchor pairs of the group of anchors to wirelessly transmit REQ messages by the first anchors during a respective first ranging slot and to wirelessly transmit RSP messages by the second anchors during a respective second ranging slot such that each pair of the plurality of anchor pairs includes an initiator and a responder operating during a respective ranging round of the plurality of ranging rounds, wherein the one or more mobile devices overhear the REQ messages and RSP messages being transmitted between the plurality of anchor pairs, calculate a TDOA measurement based on the REQ messages and RSP messages, and calculate location information based on the TDOA measurement, wherein the location information includes coordinates of the one or more mobile devices within a demarcated area, a speed of travel of the one or more mobile devices over a time period, a trajectory of the one or more mobile devices, and an angular orientation of the one or more mobile devices relative to a second subset of the group of anchors.