PURPOSE: To enable a current location to be estimated highly accurately by outputting a data from a GPS position-measuring means when a PDOP value is equal to or less than a specified value, a speed data from a GPS position- measuring means is equal to or more than a specified value, and a difference between the speed data and a speed data from a free-standing type position- measuring means is without a specified value. ;CONSTITUTION: A GPS-type position operation means 5 calculates a current position of a reception point based on a signal from a GPS receiver 4 and then outputs a data to a data-processing means 9. Also, a free-standing type position operation means 8 calculates a current position, etc., of a reception point based on a signal from an azimuth sensor 9 and a speed sensor 7 and then outputs the data to the means 9. Then, the means 9 allows either a data from the GPS position-measuring means 1 or that from a free-standing type position-measuring means 2 to be selected, map matching to be performed based on the selected data and a map information around a current position which is obtained from a memory device 10, and then a current position of a reception point to be displayed on a display device 12.;COPYRIGHT: (C)1993,JPO&Japio
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