Wireless terminal positioning method and apparatus

DETAILED DESCRIPTION An object of the present invention is to improve precision in estimation.
According to the present invention, the triangulation method is used to calculate a plurality of estimated positions relative to various combinations of three base stations selected from among three or more base stations.
The estimated positions are averaged in order to reduce an error of an estimated position.
According to the triangulation method, as shown in FIG.
5, if three unit vectors originated from a terminal towards three selected base stations are added up, an error of an estimated position becomes minimal when the length of the resultant composite vector is zero.
As the length of the composite vector gets longer, precision in an estimated position of a terminal deteriorates.
As long as the length of the composite vector falls below a certain threshold value, an estimated position contains a small error.
As an easy judgment, it may be judged whether a terminal lies within an estimated triangle, that is, whether the length of the composite vector is equal to or smaller than 1, in order to make the judgment for a short period of time by employing a digital computing apparatus.