Patent ID: 7965229

Claim:
A positioning method, comprising: capturing a satellite signal from a positioning satellite; predicting a state vector including a position of a positioning device and a velocity of the positioning device based on the satellite signal; predicting a first distance-equivalent value indicating a distance between the positioning satellite and the positioning device; measuring a second distance-equivalent value indicating a predicted value of the distance between the positioning satellite and the positioning device; calculating an observed value indicating a difference between the first distance-equivalent value and the second distance-equivalent value; setting a measurement error for the positioning satellite based on a signal strength of the satellite signal; changing the measurement error based on a capture data indicating a data of capturing of the satellite signal, the capture data being an integration time; and correcting the state vector using the observed value, and the changed measurement error, the capturing of the satellite signal including calculating a correlation value and integrating the correlation value, the changing of the measurement error including at least changing the measurement error based on the integration time in the integrating of the correlation value.