PURPOSE: To mutually confirm the positions of terminal devices owned by the members of a group by receiving the position transmitted from the other portable terminal device by the respective portable terminal devices.
CONSTITUTION: The members of a group respectively have portable terminal devices 100a, 100b, 100c. The devices receive radio waves from GPS satellites 190a, 190b, 190c to specify the respective present positions. The devices 100a, 100b, 100c respectively have communication units, and exchange data among then. The devices 100a, 100b, 100c detect the positions by using them and respectively display them on screens. The devices 100a, 100b, 100c can externally obtain map data, display the members' positions on the maps displayed on the screens, and confirm the members' presences at a glance. Further, the devices can display the member's moving speeds and directions from moving speed information, and know that the members move toward correct directions.
MESE MICHIHIRO
SHIMIZU HIROSHI
