PURPOSE: To perform trouble-free, stable surveying by avoiding obstacles accurately and promptly during surveying using a GPS.
CONSTITUTION: Antennas 12 and 17 both of which can receive satellite signals SS emitted by an artificial satellite 1 are installed on a vehicle 42 in such a manner that the receiving position 12a of the antenna 12 is located on the arrow-A side of the receiving position 17a of the antenna 17, and that a distance L is secured between the receiving positions 12a, 17a. The number of satellites trapped and an index of satellite arrangement are computed from the satellite signal SS received by the antenna 12 and are outputted the satellite position data, and the vehicle 42 is moved in accordance with the satellite position data outputted, and the proper surveying is carried out using the satellite signal SS received by the antenna 17.
TAKADA TOMONORI
SAKURAI HIROSHI
