To accurately grasp movement history by making a moving body acquire an electrical characteristic including field strength of a radio wave sent from a radio base station as a measured result, producing positional candidates for a moving path via prescribed steps and identifying the path of the moving body by using the positional candidates for the movement path.
When an electric characteristic including field strength of a radio wave which is measured from moment to moment and is sent from a radio base station is acquired through a radio base station as a measured result and a prescribed electric characteristic value coincides with the acquired measured result, the movement distance of a moving body is calculated from a measured time. Positional candidates for movement path are produced by calculating an intersection of a circle having a radius equivalent to the movement distance and a field strength curve or the coordinate of a contact, making the intersection or a positional coordinate of the contact the coordinate of positional candidates and successively recording the coordinates. When the moving body completes its movement, the path of the moving body is identified by using the positional candidates for the movement path.
TAKAHASHI KAZUHIKO
OTANI YOSHIMITSU
NAKAJIMA HIDEKI
