| 摘要 |
PURPOSE:To enable a mobile station to calculate the difference in the distances to base stations from deviation in reception interval and also calculates its position by sending radio waves from >=3 base stations which are not on the same straight line at intervals of time which is known. CONSTITUTION:The base stations 1-3 send radio waves 11-31 and the mobile station 4 discriminates between reflected waves and direct waves in consideration of the continuity of reception time by using its moving speed to calculate real reception time differences t11, t21, and t31. Then, a position calculating means converts the reception time differences into the distance differences from the base stations. The tracks (parabola) of the equal-distance differences from two optional base stations are fund and the intersection of three parabolas is the real position of the moving body. Consequently, measurement errors are not integrated, there is no limitation of the utilization time, and the facility cost is low. |
