| 摘要 |
<p>To determine a location of a client device in a wireless network having at least first and second network devices (base stations), with known locations, one of the network devices transmits a first message to the other network device and the other network device responds with an acknowledgement message. One (or both) of the network devices also transmits a further message indicating actual times at which the first and acknowledgement messages were processed by itself. The client device receives the first and further messages, and possibly a broadcast message indicating the network device locations, and determines its location based on the times at which it received the messages and the difference between the actual processing times. This location may be refined by determining an angle between the client device and at least one of the network devices having multiple antennas and being configured for steered beam communications. Round trip times to each of a plurality of base stations may also be determined, or the client device may remain passive. The system determines the hyperbolic difference in distance to the two network devices without needing to know the delay between its antenna and processor or that of the base stations. Three or four network devices give position.</p> |
