Patent ID: 8565133
Filing Date: 2013-10-22
Classification: G01S,H04J

Abstract:
1. A method of providing synchronization-free station locating in a wireless network, the wireless network including a first device having an unknown location and a second device having a known location, the method comprising: (a) sending a first packet from the second device to the first device, the first packet being one of a unicast packet and a probe response packet, the first packet having a time of departure TOD(D); (b) receiving the first packet at the first device, the first packet having a time of arrival TOA(D); (c) sending an acknowledgement packet from the first device to the second device, the acknowledgment packet having a time of departure TOD(D_ACK); (d) receiving the acknowledgment packet at the second device, the acknowledgment packet having a time of arrival TOA(D_ACK); and (e) computing a distance between the first device and the second device using a first difference between the TOA(D_ACK) and the TOD(D) and a second difference between the TOD(D_ACK) and the TOA(D); (f) moving the second device to another known location and repeating (a)-(e); and (g) using a plurality of computed distances between the first and second devices to determine a location of the first device.