INITIAL POSITION DETERMINATION METHOD, POSITIONING METHOD, AND POSITIONING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a new method which determines an initial position when a positioning operation is performed.;SOLUTION: In the initial position determination method, a frame which is in the position range assumed to include a location of a mobile phone 2 is set on the earth, and the candidate position called a grid is arranged with a grid shape in the frame. For each of a plurality of the grids, a difference between a fraction part of geometric distance between GPS satellite and a fraction part of the observed pseudo-distance is calculated as a first APR value, then, it selects into N pieces of grids at order with the small first APR value. Assuming that the selected N pieces of grids are as temporary initial positions, a position convergence operation is performed based on GPS satellite signal, and further the grids are selected into M(N) pieces. For each of the selected M pieces of grids, the difference between the geometric distances between GPS satellite and the observed pseudo-distance is calculated as a second APR value. The grid having the minimum second APR value is chosen as the initial position for using the positioning operation.;COPYRIGHT: (C)2010,JPO&INPIT