| 摘要 |
PURPOSE:To perform a positioning operation by means of a combination which is suitable for a continuous positioning operation by a method wherein a direction- indicating part which designates a satellite-searching direction is installed and a satellite in a good-visibility direction is searched preferentially. CONSTITUTION:When a button in a direction which is suitable for a satellite-searching operation is selected out of buttons A to H in eight directions at a direction-indicating part 11, a detection part 2 takes out a navigation message preferentially from the satellite in the direction. A positioning part 3 analyzes the navigation message; it computes the present position and the present time of the satellite. An operation part 6 computes the directional distance of its present position with reference to a target point and the like which are stored in a storage part 5; a display part 7 displays various pieces of data. When the indicating part 11 is operated, e.g. in a vehicle moving in a city street, the buttons A and E are selected because the visibility in the front and the rear is better than that on the right and the left. Thereby, satellites, on the front and the rear, whose visibility is better are searched preferentially, the possibility that the captured satellites are missed becomes low, and a positioning operation can be performed by means of a combination which is suitable for a continuous positioning operation. |
