| 摘要 |
A method and system are disclosed by which a round-trip calculation is used to determine the distance between a mobile radio station (MS) and a radio base station (BS) using the apparent uplink and downlink signal propagation air-times (e.g., T-up and T-down). As such, no absolute time reference is required. The MS and BS report to a service node in the mobile network the local departure and arrival times of the uplink and downlink signals, and calculate the apparent air-times, T-up and T-down. The distance, D, between the MS and BS can be calculated as D=c(T-up+T-down)/2, where "c" equals the speed of light. The distances, D1, D2 and D3, to at least three base stations whose locations are known, can be used in a triangulation algorithm to determine the MS's position. |
