Patent ID: 9277369
Filing Date: 2016-03-01
CPC Classification: G01S,H04L,H04W

Claim Text:
1. A method for determining the location of a client device in a wireless network including the client device and at least one other network device having a known location, the method comprising: determining a RF delay of the client device by performing, at the client device, a transmission-to-self calibration; receiving, at the client device, a first message transmitted by the other network device to the client device; transmitting, from the client device, an acknowledgement message to the other network device in response to receiving the first message; receiving, at the client device, a second message transmitted by the other network device to the client device, the second message including an indication of a difference between a receipt time of the acknowledgement message at the other network device adjusted for an RF delay of the other network device determined at the other network device by a transmission-to-self calibration and a transmission time of the first message from the other network device; and calculating, at the client device, the location of the client device based on a receipt time of the first message at the client device, a transmission time of the acknowledgment message from the client device, the indication of the difference included in the second message, and the known location of the other network device.