| 摘要 |
In the present invention, a mobile station (2) transmits a first radio signal (S1), and a reference station (3) transmits a second radio signal (S2). Fixed stations (4)-(6) extract phase differences (Δφmf1)-(Δφmf3) between a carrier included in the first radio signal (S1) and reference clocks (Cf1)-(Cf3) of the respective fixed stations (4)-(6), respectively. The fixed stations (4)-(6) extract phase differences (Δφsf1)-(Δφsf3) between a carrier included in the second radio signal (S2) and the reference clocks (Cf1)-(Cf3) of the respective fixed stations (4)-(6), respectively. A server (7) cancels phase offsets (φf1)-(φf3) of the respective fixed stations (4)-(6) by using information on the phase differences between the mobile station (2) and the fixed stations (4)-(6), respectively, and information on the phase differences between the reference station (3) and the fixed stations (4)-(6), respectively, obtains information on distances between the mobile station (2) and the fixed stations (4)-(6), respectively, and calculates the position of the mobile station (2). |
