| 摘要 |
PURPOSE: To acquire a data indicative of the azimuth at a specified position, viewed from a GPS signal receiving section, correctly from the current position data of the GPS signal receiving section and the positional data of the specified position even when the GPS signal receiving section is in quiescent state. CONSTITUTION: Current position and a specified point of a GPS signal antenna section 11 are made to correspond to the points on the surface of a globe assumed as a sphere thus determining the coordinates of north pole, south pole, and the points corresponding to the current position of the GPS signal antenna section 11 and the specified position in an orthogonal triaxial coordinate system having the center of the globe as an origin and one axis passing the north pole or the south pole. A detecting section 34 calculates the azimuth of specified point viewed from the current position of the GPS signal antenna section 11 using an imaginary plane touching each coordinate thus determined and the surface of the globe assumed as a sphere at the point corresponding to the current position of the CPS signal antenna section 11 thus obtaining a data indicative of the calculated azimuth. |
