Patent ID: 8482459

Claim:
A positioning device comprising: a reception unit for receiving a signal transmitted from a positioning satellite; a time counter for counting time; a first reception controller for intermittently receiving time information from the positioning satellite through the reception unit; a time revising unit for revising the time counted by the time counter based on the received time information; an error calculator for calculating an error per unit time in the time counted by the time counter based on the received time information and the time counted by the time counter; a time correcting unit for calculating corrected time by removing an error from the time counted by the time counter based on the calculated error per unit time; a positioning unit for acquiring a signal of the positioning satellite by using the corrected time and measuring a position of the positioning device based on the acquired signal; and a variation detecting unit for detecting an external factor causing variation in precision of the time counter or directly detecting variation in the precision, wherein the error calculator re-calculates the error per unit time when the precision of the time counter is determined as being varied based on a detection result of the variation detecting unit.