To extend the areas where a mobile handset can determine its position using radio
waves, the present invention provides a mobile handset that is equipped with both
position calculation means using radio waves from GPS satellites and position calculation
means using RF carriers from cellular base stations. Positioning results obtained
from both of these position calculation means are combined and weighted with GPS
positioning reliability and cellular positioning reliability, respectively. A weighted
mean of these results is then output as a final position calculation result.
