Patent ID: 9476720
Filing Date: 2016-10-25
CPC Classification: G01C

Claim Text:
1. A terminal device includes: a communication state obtain unit obtaining a state of wireless communication for a movable body; a travel locus information generation unit generating travel locus information that associates each of positions along a travel direction of the movable body with the state of wireless communication at each of the positions of the movable body; a reference locus information obtain unit obtaining reference locus information, the reference locus information including the travel locus information regarding a past travel of the movable body or other objects, and at least one position in the reference locus information referring to a feature point defined as an absolute position; a measurement unit obtaining a position of the movable body along a travel direction based on a matching between the travel locus information and the reference locus information and a finding of a positional relationship between the feature point and the position along the travel direction; an mismatch detection unit detecting one of (i) a degree of mismatch in the matching by the measurement unit and (ii) a cause of mismatch in the matching by the measurement unit; and a filtering unit filtering at least one of the travel locus information and the reference locus information, a method of the filtering being preset according to one of the mismatch and the cause of the mismatch, wherein the measurement unit performs the matching before the filtering by the filtering unit, which increases the measurement accuracy of the terminal device.