Patent ID: 8125970

Claim:
A ranging method for measuring a distance between a central node and an equipment node in a beacon wireless personal area network, said ranging method comprising: (1) a central node of a beacon wireless personal area network calculating a network active period parameter in a ranging request beacon frame according to an initial value of a ranging parameter, and setting a beacon frame sending period parameter equal to the network active period parameter; (2) the central node copying an address of each of equipment nodes from an equipment address list into a measuring address queue; (3) the central node copying the address from the measuring address queue into the ranging request beacon frame sent from the central node to the equipment nodes, and broadcasting the ranging request beacon frame to the equipment nodes, each of the equipment nodes in turn sending a ranging frame to the central node at an assigned time slot according to the address in the received ranging request beacon frame; (4) if the central node receives the ranging frame at a unit time slot, the central node recording an arrival time of the ranging frame from the equipment node, and the central node copying a new equipment address from the measuring address queue into the ranging request beacon frame until the assigned time slots of the equipment nodes end; (5) repeating steps (3) and (4) for completing a first ranging of each of the equipment nodes; and (6) calculating an average value of the arrival times, and getting the distance between the central node and the equipment node according to the average value and the initial value of the unit time slot corresponding to each of the arrival times.