Patent ID: 6785609
Filing Date: 2004-08-31
Classification: G01S

Abstract:
A hybrid processing method of outputting current position data, which indicate a current position of a movable body on which a self-contained positioning device and a GPS device are mounted, on the basis of self-contained positioning data from the self-contained positioning device and GPS measurement data from the GPS device,said method comprising: a judgment process of judging whether or not an estimated error of the self-contained positioning data is greater than a predetermined threshold value; a first calculation process of calculating the current position by combining the GPS measurement data with the self-contained positioning data if the estimated error is judged not greater than the predetermined threshold value; a second calculation process of calculating the current position from the GPS measurement data without combining the GPS measurement data with the self-contained positioning data if the estimated error is judged greater than the predetermined threshold value; and an output process of outputting the current position calculated by said first or second calculation process as the current position data which indicate the current position of the movable body, wherein said judgement process performs the judgement before elapsing a predetermined period from a time of switching on a power of the self-contained positioning device, and if the judgement is not performed, the present position is calculated by the first calculation process.