NAVIGATION DEVICE

PROBLEM TO BE SOLVED: To provide a navigation device capable of enhancing precision of the shape of a non-registered road by enhancing the accuracy of decision whether it is the non-registered road to be registered. SOLUTION: The navigation device includes a GPS sensor 11 for detecting current position; a reference value modification part 18 for modifying a reference value for evaluating the receiving state of the GPS sensor; a detecting part 14 for detecting the non-registered road, based on position information from the GPS sensor and for generating the non-registered road information, including GPS receiving state data calculated by comparing data relating to the receiving state of the GPS sensor with the reference value concerning a plurality of measuring points of the non-registered road; a determination part 15 for determining whether it is a non-registered road to be registered on map data, based on the GPS receiving state data, included in non-registered road information and the reference value modified with the reference value modifying part; and a registering part 16 for registering the non-registered road detected with the detecting part, when it is determined that it is the non-registered road which should be registered on the map data by the determination part. COPYRIGHT: (C)2009,JPO&INPIT